Eric's Hi-Fi Blog

Calyx Coffee DAC and Headamp

2012-01-03T21:06:00.001-08:00

Good things come in small packages ! Well this does not always hold true for audio equipment, but nevertheless, the Calyx Coffee is really diminutive and cute as a button to boot.

The Calyx sports the current in-thing for DAC chips, the ESS Sabre. At the Calyx’s asking price, you obviously luck out if you were hoping to get the Reference Sabre chip. Instead, you get the ES9023 which sports two D/A convertors (vs. the eight found in the Reference). Like the rest of the Sabre chips, the ES9023 also boasts technology such as Hyperstream Architecture and Time Domain Jitter Eliminator (the complex technical details of which overwhelm my feeble mind).

Interestingly, the ES9023 chip includes a 2VRMS driver which would presumably allow a designer to skip the op-amp stage and use the ES9023 as a single chip solution.

On the bright side, your hard-earned money gets you a 24/96khz capable DAC with asynchronous USB connection, and a fairly competent headphone amplifier. The most obvious target market for the Calyx would be in a computer based head-fi or desktop set up. Given its small size and portability, it is also the perfect traveling companion, and was in fact the reason I purchased one. Pack in a nice pair of earphones with your notebook and the Coffee, and suddenly your work trips do not seem so lonely after all.

Dressed in a shade of a rather weak looking cup of Java, the Calyx is a simple bar shaped device. On one end, you will find its single USB input, and on the other, a pair of RCA outputs, and a 3.5 mm headphone jack.

The top of the unit is adorned with a single neat row of small gold buttons, that can control the source computer, with the ability to control play, skip and volume control (including mute). Stick on rubber feet are provided, so no worries about marring the beautiful surface of the Calyx. No cables of any form are provided, which is fine with me. Most freebie cables end up in the dustbin anyway. The Calyx draws its power from the computer’s USB port and there is no option to power it from an external 5V power supply.

Shaking the unit results in an alarming rattling sound. I was worried that something was broken inside, but the dealer assured me that it was just the buttons. True enough, the rattling stops if you apply a bit of pressure on them. Other than that, build quality is excellent. There are no screws or joints on the top and sides of the unit, so the Calyx is presumably milled from a single aluminum block. The bottom plate is screwed on though, making the enclosure of the Coffee a two piece assembly.

Installation was straight forward and hooking up the Calyx to my computers running Windows XP and Mac OS Lion were hassle free. No drivers were required and the Calyx was immediately recognized. Everything worked as expected, including the operation of the buttons to control the volume, etc. The steps were a bit coarse though, and I ended up using the slider bar on Windows to control the volume of the Calyx.

The Calyx Coffee has enough juice to drive most ear or head-phones on the market. It certainly had no problem driving either my 250 ohm Beyer DT-880 or my Audeze LCD-2. With the latter, volume is almost maxed out, so LCD-2 users who listen very loud may want to look elsewhere.

Sound quality is good, well above average and far better than you expect for its price.

Hooking up the Calyx to my main hi-fi system, I questioned the sanity of using cables (Acrolink 7N-D5000 RCA and LAT International USB 2) which were more than 8 times the cost of the Calyx. I then awaited for the David vs. Goliath moment. After a few minutes, it was obvious that my Audio-gd DAC 19 was in no danger of being outclassed by the Calyx. The Audio-gd is close to 4x the cost of the Calyx, so no surprises there.

The Calyx has what I consider to be the typical Sabre house sound - slightly laidback and hyper-detailed. Sabre chips do not have the incisive leading edge emphasis of more analytical chips, but instead presents its sonic picture in a natural way. The details are all there, but are not presented with the stark contrast and leading edge emphasis of some of its competitors.

Bass is firm and slightly full. However, it lacks slam and extension. Bass freaks will definitely not be satisfied. You could say that the Calyx is slightly bass shy but the overall quality of its limited bass is quite high.

Midrange is one of the Calyx’s stronger points with a smooth and natural human voice. The usual suspects of sibilant tracks are quite well behaved and it is unlikely that this DAC will come across as cold or harsh. Listening to Eva Cassidy's album, “Live at the Blues Alley”, you get a sense that the Calyx chooses to honey coat things. The usual sibilance and slightly piercing quality of Eva sounds very nice on the Calyx – a bit too nice to be true.

High frequencies are clean and fast, and the sense of acoustic space is well conveyed. Nevertheless, treble extension could be better and is easily bettered by more expensive equipment.

Imaging is good, but soundstaging is slightly flat, with a reduced perception of width and depth in recordings. This is very noticeable as a loss of presence and air on Janos Starker's recordings of Bach's Suite for Solo Cello. Instruments and voices are also placed further back than my usual gear, with slightly smaller image sizes.

The Calyx is also not the most dynamic DAC out there. Rock and metal lack some energy and rawness. Faster music sometimes comes across as being a bit too polite.

Detail wise, the Calyx is definitely a significant upgrade over a stock computer soundcard or chip. However, some level of microdetail is lost, which is apparent when compared to the Audio-gd.

The weaknesses of the Calyx Coffee should be viewed in context of its affordable price. When used without reference to better (and much more expensive) equipment, the Coffee is musical, offers a useful upgrade in resolution and is pleasing to the ear. It gets a lot of things right, with good tone, especially for those with a musical diet tuned more towards jazz, vocal recordings and chamber music. It is only when you do direct comparisons to other gear, that you realise what is missing.

Two things I would have liked to see would be support for a RCA digital input, and support for 88.2 khz sampling rate. The first omission is forgivable since the Calyx is clearly not intended for primary use in home systems. However, the second omission is less so. The lack of 88.2 khz sampling support deprives native decoding of some source material out there (admittedly quite rare), as well as 2x up-sampling of red book material. My personal experience with red book up-sampling, is that it sounds more natural up-sampled to 88.2 khz compared to sample rate conversion at non integer multiples, e.g. 96 khz. I know what many will say, the big brother Calyx DAC is the answer to my wish-list.

In summary, the Calyx is a great upgrade for computer audio users. It is very competitively priced and competent. I am very impressed with the Calyx Coffee and recommend it highly for a portable computer based setup, and even more so, if primary listening is being done through head or ear phones. If using inefficient or difficult to drive headphones, I would advise you to try before you buy.

For home rigs, the Calyx is a less convincing proposition. While it is adequately suited for budget rigs, spending a bit more would definitely pay more dividends in the long run. Then again, for the money, you certainly could do a lot worse.

Diary of a newcomer to the dark side

2011-11-21T21:47:00.000-08:00

Day 1

Toying with the idea of buying a new turntable to complement my existing one (Bluenote Piccolo / Rega RB300 / Ortofon MC15II). The present turntable sits in my bedroom system and it would be nice to be able to spin my records in my main setup. The present setup is decent but not awe inspiring.

A frantic search on the internet ensues. A list of suspects is formed, Rega, Pro-ject, etc.

Day 4

A visit to the Pro-ject dealer, House of Turntables is made during lunch. The friendly duo at the House of Turntables let me listen to the Pro-ject RPM 5.1 with Denon DL-160, as well as the Pro-ject 2 xperience Acryl with the Sumiko Blackbird. Both setups are mindblowing and definitely better than my Bluenote (I believe the MC15II is on its last legs). Payment is made for the 2 xperience as well as the Pro-ject Phono Box SE II and Speed Box II, and following that, is 5 excruciating days of waiting.

Day 8

An evening trip is made to Ikea to buy a chopping board to use as a base. The rack in the main room is full and the turntable will need to make do with a platform resting on the floor. I put some spare DH Cones and pads underneath the board. A small desk lamp is purchased too as the room is quite dark, and my eyesight is not the best.

Day 9

Kevin of House of Turntables shows up at my doorstep in the evening to deliver the deck and to help set it up. We spin a Jacintha record and we both proceed to pick up our jaws off the floor. Spent most of the night listening to records.

Day 10

Bought some new records. Bought some record cleaning fluid and new LP sleeves. Spent most of the night listening to records.

Day 11

Bought some more records. Spent most of the night listening to records.

Day 12

Spent most of my waking hours (OK, I'm exaggerating a bit here) wondering whether I should have bought a better phono stage, and whether my loading is correct. Experimented with loading and left the Sumiko at MM settings (47 kOhm). The gain is a bit lower than usual, but the MC stage has a maximum resistance loading of 220 Ohms which is a bit too low for the Sumiko.

Day 15

Cleaned some of my dirty records. They sound great. I was almost ready to check them out.

Day 16

I start pondering on the benefits of upgrading my phono stage again.

I finally realised what the whole fuss was about. Good vinyl is good.... very good. It just needs a bit of work and effort to get it right.

Next step is to replace that ageing Ortofon cartridge for the Bluenote. I decided on the Dynavector 10x5. Unfortunately it was out of stock, so I have to wait until next month.

Never mind, good things come to those who wait.

TAOC Tite-13GS

2011-09-17T23:43:00.000-07:00

The TAOC Tite-13GS is tiny, especially compared to its much larger and heavier siblings in the TAOC range.

Picture from TAOC's official website

Measuring just 25 mm in diameter and 10 mm in thickness, each piece weights 30 grams. Sold in a set of 8, their primary use is to act as an isolation disc in between the base of bookshelf speakers and speaker stands.

Apart from that, their use is limited only by your imagination. The local dealer suggests that you can also use them as equipment footers to support very small equipment (like USB/SPDIF converters, power supply boxes etc), or on top of equipment to damp chassis resonance.

I tried a single piece each on top of my Audio-Gd DAC-19 and Kingrex PSU-MkII. Initial results were not encouraging, with the tonal balance simply feeling a bit unnatural. After some experimentation, they ended up close to the transformers. Interestingly, they sounded better off center, rather than directly over the transformer.

In typical TAOC fashion, there is a slight improve in focus, and noticeable improvement in midrange and bass texture and weight.

They cost about SGD 140-180 for a set (depending on promotions offered by the local dealer).

To be continued...

Proac Response D1

2011-09-17T23:41:00.000-07:00

Introduction

The Proac Response D1 is the successor to the Response 1SC. The 1SC was quite popular in this part of the world. Given that our listening rooms are typically quite small (3x4m being about the average size of a bedroom here), there is a big market for high performance speakers that can perform well in smaller acoustic spaces.

Physically, the D1 is a compact (30.5 cm high, 16.8 cm wide, 26 cm deep), but heavy (9 kg) bookshelf speaker.

Available in a wide variety of real wood veneers, the D1 has exemplary finishing and would not be out of place in a picture spread of a home interior magazine.

The D1 in Cherry veneer - Pretty as a picture !

The D1 is a larger speaker than its predecessor, especially in terms of depth. The tweeter drive unit seems similar (a custom Scanspeak silk dome model), while the bass / midrange unit has been changed. The 1SC woofer has a transparent cone with cooper phase plug model, while the D1 has a black glass fiber cone with acrylic phase plug.

Custom ordered Scanspeak silk dome tweeter

Note the acrylic phase plug

Rhodium plated bi-wiring terminals

On paper, the D1 has slightly better efficiency (87.5 db / 1W / 1m) than the 1SC (86 db / 1W / 1m). Both speakers are rated at a nominal 8 Ohm impedance.

The D1 also is claimed to have improved cabinet damping and crossover parts over the 1SC.

Bi-wiring terminals are provided.

Partnering Equipment

The D1 was placed on Atacama SE24 stands (1/3 filled with sand) in my 3 x 3.5 meter listening room. They were pulled out approximately 70 cm from the rear wall.

Partnering equipment is as follows :-

Source

Squeezebox Touch as transport (powered by Kingrex PSU-Mk II power supply)

Pioneer PD-77 CD player as transport

Audio Gd DAC-19 DSP

Amplification

Cary SLI-80 Signature Special Edition integrated tube amplifier (Shuguang Black Treasure KT-88 power tubes, Mullard 6922 preamp tubes and Tungsol re-issue 6SN7 driver tubes, Cetron 5R4 rectifier tubes)

Accessories

Oyaide DR-510 digital cable

Canare L5-CFB digital cable

Acrolink 7N-A2070 interconnect

Oyaide Tunami power cord (Cary)

Acrolink 6N-P4030 power cord (wall to distributor)

Acrolink 6N-P4030 power cord (Kingrex PSU)

Acrolink 7N-P4030 power cord (Audio-Gd)

Acrolink 7N-S1000 speaker cable

Performance

I have never heard the 1SC and therefore can only make direct comparisons with the Tablette 50, which I owned for a number of years.

I experimented with speaker positioning and listened to the speaker for about a week before settling down to make some detailed notes. My speaker cables on hand are terminated for single wiring, so I used some high quality jumper cables to facilitate single wiring.

Pairing was only attempted with tube amplification, as my past experience with Proac speakers is that they work exceptionally well with glowing tubes.The D1 liked my Cary more. Although it had excellent tone with my Almarro A-318B, there was a lack of grip and extension. Given its average sensitivity, I would not try the D1 with single digit watt tube amps or other flea powered amps.

Giving the speakers a quick spin, the first thing that strikes you is the excellent integration between both drive units. The second thing is the pin-point imaging and soundstaging.

Coming from my usual speakers, the Focal Micro Utopia Be, my mind had to adjust for the lack of scale and bass weight. But once this is done, you get used to the somewhat lightweight but high quality tight and tuneful bass on offer. It lacks the slam needed for heavy metal and orchestral pieces, and is more suited for the listener with a music diet of jazz, chamber music and vocal works.

The Tablette 50 in comparison has significantly more colouration in the upper bass, with a noticeable chestiness. The D1 sounds a lot more open and avoids the more technicolour presentation of the Tablette 50. I believe that the far better constructed cabinet of the D1 has a part to play in this, with better damping, bracing, and less resonance.

I noticed also that the D1 became more comfortable as the volume knob was advanced. It is quite unflappable even at rather anti-social volumes. The bass comes alive and the initial impressions of a lightweight bass go out the window at moderate volumes. Of course, the law of physics cannot be changed, and low frequency output is limited. However, the bass does belie the physically small dimensions and is tuneful and fast. From a PRAT perspective, the D1 scores top marks. Looks like the D1 is not really for those late night, low volume listeners then.

The D1 has all the hallmark strengths of the Proac brand, like a communicative midband, and a high level of transparency. From a presentation viewpoint, it avoids the hyper detailed and analytical approach, preferring to present musical information in a coherent, and musical manner.

The midband in particular is to be praised for striking the right balance between being open and smooth. Cai Qin sounds suitably rich and weighty, but without obscuring detail. Eva Cassidy still sounds clear and at times piercing (this is inherent in many of her recordings).

High frequencies are quite well extended and clean. The tweeter unit is not the most resolving, but is always well behaved.

On the D1’s weaknesses, a small amount of spatial information and microdetail are lost. Although imaging and soundstaging are precise, they tend to be flatter in perspective compared to class leaders. Listening to familiar materials like Eva Cassidy’s Live at the Blues Alley, and various Patricia Barber albums, I noticed a lack of perception of image depth and height. Instruments and voices are conveyed accurately, but the timbre and texture, as well as the air around the instruments and the singer are not resolved as well.

Violin pieces sound sweeter than usual and there is a slight lack of bite and feel for the resonance from the instrument’s body. This cuts both ways, since it also flatters poor recordings. Thankfully, Piano has the correct timbre and tone, with good attack, weight and feel for both the hammer strike and frame / soundboard.

Conclusion

The D1 is a nice bookshelf speaker. Well suited to bedroom and small listening setups, it is a very competent performer and is engaging and entertaining.

However, price wise, at more than S$ 3,000 per pair, it is expensive for its performance, and faces very stiff competition. It does not suit all musical taste, and will not satisfy the detail spotters. The lack of low frequency extension rules out heavy rockers and metal lovers.

Acrolink Power Cords - A relook into conductor purity

2011-05-30T22:20:00.000-07:00

Quick Comparison Table

Model               Price     Gauge        Conductors       Shielding       EMI absorbing cord

7N-P4020III   $90/m    Medium     0.26mm x 37    Copper tape Yes

6N-P4030       $160/m  Large        0.26mm x 100   None            Yes

7N-P4030II     $200/m   Large       0.26mm x 100   Copper tape Yes

For purposes of a fair comparison, all cords mentioned were terminated with Oyaide P-004/C-004 connectors, which are the matching plugs for the Oyaide R-1 AC outlet used.

7N-P4020III

The smallest cable of the lot (by gauge), the 7N-P4020III is supremely flexible and a cinch to strip and terminate.

It is considerably more detailed than the 6N-P4030 with better “look-through” and high frequency extension. Both transient and ambience definition is improved.

In the lower frequencies, it appears to be less weighty than the 6N-P4030. Closer comparisons actually reveal that the 7N-P4020III has deeper and tighter bass. However, the 6N-P4030 has a fuller mid-bass. Overall, the 7N-P4020III sounds tight and grippy, but with little bass bloom. It low frequency reproduction reminds me of the a Class-D amplifier, as opposed to a tube amplifier.

This cable fares well on background “blackness”, dynamics and separation. I would consider it to be a worthy upgrade in most systems and given its affordable cost, it is excellent value compared to the rest of the cables here.

6N-P4030

The 6N-P4030 is moderately easy to strip but tricky to terminate due to the large gauge of its conductors. To prevent undue strain on the clamping terminals of the Oyaide plugs, it would be best to strip a bit more of the cables than recommended and divide the raw copper strands into two equal bundles, i.e. resembling a two prong fork.

Formerly, my favourite cable (for source equipment), the 6N-P4030 has always impressed me with its refined midrange and high frequencies and its delicate reproduction of ambience and air. It has several weaknesses though. One is that the sheer amount of high frequency information makes the cable sound subjectively bright. Secondly, the equal emphasis on both the transient of the note and the decay may make some systems sound a bit slow. Lastly, it sounds very natural and gentle, and sometimes the force and dynamics of a recording are somewhat diminished.

Comparisons to the 7N siblings illustrate these shortcomings. The 7N cables sound more dynamic with deep extended bass and seemingly faster transients. Lengthy comparisons show that the 6N cable has less control and separation under heavy mixes with a slight loss of refinement.

7N-P4030II

The 7N-P4030III handles exactly like the 6N-P4030 in terms of flexibility and ease of termination.

Sonically, it combines the best of the two preceding cables. It has the mid-bass bloom lacking in the 7N-4020III while retaining its dynamics, separation, detail and speed. Subjectively the 7N cables have more background “blackness”, perhaps due to the copper tape shield. Overall, this cable sounds focused, while maintaining composure and refinement.

In terms of music, notes on the 6N-P4030 are always soft, gentle and very natural. The 7N-P4030II could be said to be more hi-fi like with a more defined and projected leading edge. The difference in presentation is unlikely to polarize fans of Acrolink cables and the basic DNA and house sound is still there.

To use a food analogy, the 7N-P4030II is like Cantonese soup from a top restaurant, flavoursome, yet crisp, clear and clean. The 6N-P4030 is more like good consommé. Always refined, flavoursome and clear, but with slightly less contrast.

Furutech FP-1363 UK AC Outlet

2011-05-23T08:53:00.000-07:00

Singapore Audiophiles do not really have much choice in installing audio grade UK wall outlets. Most make do by buying special US outlet faceplates that fit on our existing UK back boxes. This is of course in violation of local electrical codes.

Furutech is one of the few manufacturers to offer a solution - at a price. They make a single or dual outlet UK receptacle, with a choice of gold or rhodium plating. The base metal of the contact points is pure copper and treated with Furutech's proprietary alpha process, which involves both cryogenic and demagnetization treatment.

Featured here is the gold plated duplex model, FP-1363-D(G)

Plain cardboard box (with a bit of sticker shock, according to Mrs. Audiophile)

The plate is rigid and far less resonant than the stock outlet commonly used

A close up of the terminals. No problem with the beefiest of cables

A few pointers when installing these outlets. The faceplate is slightly longer than a standard socket. Measure carefully if installing them in tight corners, or adjacent to other sockets. Secondly, each outlet has an independent terminal, so make sure you have extra cable to jumper both outlets together in case your existing receptacle only has one set of wires. Lastly, the screws supplied are a bit on the short side. Probably fine if your backbox is not deeply recessed, but woefully short for my house installation.

If you do not know how to switch off your mains supply, test your circuit for live current, or to do the installation, please pay a qualified electrician to do it for you. This is not really a situation where you should be cheap.

First impressions after a 24 hour run-in of the outlet were positive. They gripped my matching Furutech FI-UK-1363(G) mains plug tightly and firmly. Apart from a refined smoothness, micro-detail was a step up compared to the stock outlet (a two year old Legrand). High frequencies were a touch cleaner and more extended. It was a subtle improvement but not of the earth shattering nature.

After a week of run in (my source equipment are left powered up permanently), the Furutech opened up slightly. The positive initial impressions remained but the refined smoothness gave way to openness without any hint of harshness. I generally find gold plated connectors a bit soft sounding, so it was a pleasant surprise that the Furutech did not dull transients or obscure detail. There is a possibility that this boils down to the mating of similar metals between the outlet and the matching Furutech UK plug used in my system.

To put things in perspective, I found greater differences in replacing power cords, or receptacles on my power distributor. The improvement brought about by changing the wall socket probably counted for a subtle but noticeable improvement in the 5-10 % region. In a top notch setup, this little bit of difference is enough to bring the system to a higher level. I would tweak elsewhere first, but for the audiophile that has done the whole works except the wall socket, this is well worth the effort.

DIY your own balanced interconnect

2011-05-02T22:26:00.000-07:00

DIY your own balanced interconnects with Mogami Neglex 2534 !

Neutrik XLR plugs, Mogami 2534 cable, paper cutter, Kester 44 solder and Teflon plumbers tape

The Mogami Neglex 2534 is a flexible shielded star quad cable, i.e. separate shield and four individually insulated conductors. I have used this cable in both single ended and balanced applications, and this cable really shines in balanced form. Singapore readers can get this cable from Team 108 in Macpherson. You can have a look at their website for contact details and opening hours, http://www.team108.com/

Once you have cut your cable to length, slide the rear plug housings on to the cable. I have lost count of the number of times I have soldered cables happily only to realise that I forgot the backshell !

Strip the cable and conductors, and twist the same coloured conductors together, i.e. form two conductors by twisting the clear cables together, and repeat with the blue cables. Bundle the shield wires together too.

I would suggest tinning the cable ends once you are done.

For plugs, general convention is male on one end, and female on the other. Check your equipment to be sure - I've seen some funky equipment that do not follow this.

Solder the shield to pin 1. Then solder the two conductors to pin 2 and 3. It doesn't matter whether you solder the clear cable or blue cable to pin 2 or 3, just make sure you are consistent on both ends.

Once you are done, it would make sense to wrap the exposed parts with a bit of plumbers tape. Other good practices would be to clean all parts, including the stripped wire with a bit of isopropyl or denatured alcohol, before soldering.

The 2534 may just surprise you. To my ears, it sounds as good as many other expensive balanced cables that shall remain nameless.

12AX7 tube comparisons

2011-05-01T22:54:00.000-07:00

Here is a quick comparison of new 12AX7 tubes tried recently. All new tubes had at least 20 hours of burn in time on them.

From left, RCA 5751, Sovtek LPS, Tungsol re-issue, Psvane, GE Triple Mica Black Plate 5751. My morning cup of coffee just happened to be there.

Tungsol re-issue (steel pin)

Following from my review of Tungsol's 6SN7, a quick audition of its 12AX7 brother suggests that New Sensor is going for a particular house sound with Tungsol re-issues. Predictably, the 12AX7 sounds smoother, richer, with more bass emphasis compared to its EH cousins.

The Tungsol has a creamy smooth midrange with a weighty and slightly rounded bass. The trade-off is comparatively less open highs. Brass instruments and the shimmer from hi-hats have noticeably less rasp and decay. This also affects the retrieval of fine acoustic space. The lower register weight helps Piano notes though which have impact and good timbre.Resolution and dynamics are mediocre.

BTW, like the Sovtek LPS, don't chuck them out if they "fail" to light up. The filaments are so deeply recessed that the tubes do not glow when switched on.

Sovtek LPS

If the Tungsol is "night", then the Sovtek LPS is certainly "day". Not to be confused with the standard Sovtek offerings, the LPS is a Long Plate Spiralled filament version.

The Sovtek has a very tight and focussed sound, against a deathly quiet background. This is far from being a dark sounding tube. Bass is tight although not particularly extended. The midrange is forward and almost solid state like, but grain free. Highs are clear and extended. Dynamics are first class. On the downside, the Sovtek tends to emphasize voice sibilance. When the mix gets really heavy, separation of instruments also tends to fall apart.

Put into perspective its low price, this is an excellent tube that is actually better than a lot of the ho-hum NOS tubes out there. It is not the best available, but could be just the ticket to opening up a dark and slow sounding system.

Psvane

A premier offering from Shuguang, the Psvane (as well as Shuguang's power tubes sold under the Black Treasure series), is sold with eye-popping prices (for a Sino tube) and rather fanciful (but ultimately useless) foam lined cardboard box with individual test results and serial numbers.

Psvane signal tubes (I had a roll with its 12AU7 brother too) seem to have one thing in common - tonal density. These are not insipid or wispy sounding tubes. They have a strong and full flavour. Bass and midrange are full and smooth. Coupled with good high frequency extension and good separation, they are well balanced and good overall performers. They are also quiet and refined sounding. Top marks for composure - they never lose their cool, even under complex and messy mixes.

In terms of ultimate high frequency extension and speed, the Sovtek LPS have an edge over the Psvane. The Psvane also tends to deliver larger than life images - perfect for the SET / full range speaker crowd.

If its tonal balance suits you, this is a very nice tube. Objectively, it is heard and shoulders above most current production tubes (and it should be - with a matching price tag). However, I could think of a few NOS tubes that could blow it out of the water, or at least give it a serious run for the money.

RCA 5751 double mica black plate

OK. The 5751 is not a 12AX7 tube. They have slightly lower gain but other than that can generally be used as a substitute for 12AX7 tubes in buffer and line level applications. My tubes were bought NOS from a well known local dealer and have at least a few hundred hours on them. They are featured here as a comparison between new tubes and NOS. Price wise, the Psvanes are almost as expensive as the RCAs.

The RCA has a nice big and wet bass. It has a rich and creamy midrange which controls sibilants well. On the downside, brass lacks bite and dynamically, this tube sounds a little bit slow. In comparison, the GE triple mica 5751 grey plate or the Sylvania triple mica gold pins are significantly faster and more open. Rather unfortunately, the tubes mentioned have become horrendously expensive as of late. For the money, I would pick the Psvane over the RCA.

Kingrex PSU Mk II - DIY DC Cable

2011-04-04T22:55:00.000-07:00

Here is a nice project for a lazy Sunday afternoon. Frustrated with your stock DC cable that comes with your Kingrex PSU ? Come on guys, the cable is far too short !

Parts List

1x Neutrik Male XLR socket
2x 1m 18 AWG Neotech 7N Teflon insulated PCOCC copper cable or silver cable
1x Switchcraft 760 DC jack (fits my Squeezebox Touch just fine)

Instructions

Step by step instructions are probably unnecessary for this simple project.

I twisted the cables together lightly to provide a bit of RF rejection. It is worthwhile to also consider using shielded cable for this purpose.

Impressions

Initial impressions were that of a more detaled midrange and larger image size. Unfortunately, the high frequencies also sounded a bit hashy and the overall sound is quite grainy. In comparison, the stock cable is smooth, with a relatively laidback soundstage. The stock cable also sounds a little bit vague and the tonal contrast is lacking.

After 10 hours of burn in, things got better. The hash and grain are still there but are less prominent. The soundstage is a lot deeper and front to back layering is more distinct. Midrange is more forward which may not be to everyone's taste.

At the 30 hour mark, the cable is well settled and refined. Instruments are firm and transients are solid and distinct. In guitar solos, you can clearly hear the pluck and reverbation of each string, together with the resonance of the guitar body. The midrange although more forward compared to the stock cable is both more full bodied and detailed.Soundstaging gets a boost too with good gains in stage width, height and depth.

With about 100 hours of burn in, the cable feels quite well settled. It is not a dramatic change compared to the 30 hour mark, but the improvements are nevertheless still significant. The cable still remains more forward compared to the stock cable, and although the treble is grain free, sibilance on female vocals is more noticeable. Piano notes in particular are solid, firm with a distinct separation between the strike of the hammer against the strings, and the resonance of the body of the piano.

In terms of sonic gains, this is at least the equivalent of an interconnect or power cable upgrade.All in all, this is an impressive upgrade for about S$ 30 in parts and less than 30 minutes of time.

If you are interested in a cost no object version, you could try using higher grade Neutrik XLR jacks (there are several different grades depending on the choice of plating of the metal pins), and Neotech's solid silver wire.

Solid Silver Wire Version

Over the last weekend, I decided to try out an improved version as suggested above. Utilising the same twisted wire construction, this cable is made out of 18 gauge Neotech solid silver cable. The cable was additionally cryo treated by the local distributor for a small premium.

Isn’t silver wire bright ? In my experience, silver is seldom bright. Silver plated copper can sound bright, but none of the solid silver cables I have handled or owned sound bright or edgy, which are common adjectives used to describe silver cables.

There were good sonic gains compared to my copper cable. The sound is similarly laidback, but imaging is more focused, and the level of fine detail is significantly better. Although the cable had only chalked up about 20 hours of burn in, it was able to outperform the copper cable by a comfortable margin.

Authority and extension on both frequency ends were enhanced, and the “atmospheric” feel of live records made it feel like you were almost there. The experience was just simply more holographic. You add about S$100 of cost, but this is money wisely spent. Given the overall low cost of making this cable, I would advise all readers to simply plump out for the silver cable version.

Brief audition of the Usher BE-718 DMD with Calyx DAC and integrated amplifier

2011-03-14T22:50:00.000-07:00

I am quite familiar with the original Usher BE-718 which uses a Beryllium alloy tweeter. The BE-718 and the X-718 that preceded it stirred up quite a lot of controversy, from its close resemblance to a certain other renowned manufacturer, to the Beryllium content (or lack thereof) of its tweeter dome.

Controversy notwithstanding, the BE-718 sounded great and I would have walked home with a pair if my amplifier had the power to drive it. Audio Basic had no issues driving it with their solid state amplifiers, but a quick hook up to a 30 watt per channel EL-34 push pull amplifier proved that these speakers really thrive on power.

Fast forwarding to the BE-718 DMD, I believe that the speaker is internally identical to the BE-718, with identical crossover points etc. Worldwide, dealers are offering the DMD tweeters to BE-718 owners as a drop-in upgrade. Local users should be aware that the domestic version is not the same as the U.S. version which sports a tweaked crossover with upgraded capacitors and internal wiring.

Driven by the Calyx DAC and integrated amplifier (100 watts per channel into 8 ohms), the BE-718 DMD sounds quite different from its Beryllium predecessor, primarily in the resolution of air and detail. The Beryllium tweeter is already quite extended and resolving, and the DMD tweeter is a further step in this direction.

Are either tweeters bright ? That depends on what you are coming from. I think they are fine and subjectively sound less bright than the Beryllium tweeters on my Focal Micro Utopia BE. Of course, a tweeter does not maketh the speaker.

On the low frequency front, the Usher has a fair amount of grunt and good low bass given its cabinet size. Bass lines are agile enough and the amount of bass should be just right for a standard Singapore sized HDB bedroom (3x4 meters).

Going up to the midrange, vocals are smooth although slightly dry. The upper midrange has a slight hardness to it and brass instruments seem more prominent compared to other speakers.

The high frequencies are the true star of this speaker, with speed, resolution and air that are truly impressive for the asking price of these speakers.

Subjectively, the Focal is a better speaker. It has more bass authority, a better midrange, and more resolving high frequencies. It also throws a bigger soundstage and can resolve front to back layering better than the Usher. The Focal also happens to be much more expensive than the Usher.

At its present promotion price, I think the Usher is an excellent buy (contact X-audio or Audio Basic directly for prices). Is it worth it for original BE-718 owners to upgrade to the DMD tweeter ? I think that it is a far more difficult proposition. The cost of the DMD tweeters as sold locally is substantial. Although the DMD tweeters sound better to my ears, I would not put that much a premium to it to justify the cost.

Last but not least, credit also goes to the Calyx duo. The Calyx DAC (24/192) offers world class resolution at affordable prices, while the Calyx integrated amp never ran out of steam, even at rather uncomfortable volume levels. The Calyx integrated amp also has a built-in DAC and USB input (24/96 only). Add a Mac Mini, Calyx integrated amp and the Usher, and you have a very nice system for around S$ 6,000. Now where were systems like this when I started out in hi-fi 20 years ago ?

Shuguang KT-88Z Black Treasure Tubes

2011-03-12T22:04:00.000-08:00

Shuguang's Black Treasure KT-88 tubes are being run-in on my Cary amp at the moment.

Visually striking, these tubes are classy. Launched to commemorate the 50th anniversary of Shuguang, the Black Treasure tubes are said to have 60 differences compared to their normal line. The most obvious is the black high polymer compound carbon coating inside.

Initial testing upon power up resulted in a loud crackling distortion that lasted about 2 seconds before disappearing one one channel. It never happened again, so I would not put too much into that.

Trawling the internet revealed user accounts of long tedious burn in (200-600 hours), with an accompanying roller coaster ride in quality in the process. It kinds of reminds me of my Mundorf Silver-in-oil burn-in experience.

Thankfully, the Black Treasure sounded quite good from the outset. With about 10 hours under their belt, initial impressions are that of exquisite refinement and quietness. Compared to the Genalex re-issues that preceded them, the Black Treasures had less bass bloom, but a more refined midrange and treble. The Genalex has more prominent bass, with a fatter upper bass that gives music solidity and heft. The Black Treasure is arguably tighter and more controlled.

The Back Treasure really differentiates itself on the midrange and treble. Apart from its inky black background, the dynamic contrast, and low level resolution were world class. Holographic presentation of instruments and voices, and the accompanying acoustic space were superb. The only fly in the ointment was the extension and air of high frequencies. Compared to the Genalex, the Black Treasures sounded restrained, and simply unable to let go. The local dealer and another hi-fi friend assures me that this disappears upon extended run-in.

I'll report back after further run-in.

Black Treasure tubes are available in Singapore from Live Acoustics, www.liveacoustics.com.sg

To be continued ...

DIY Power Distributor

2011-03-01T21:44:00.000-08:00

No money for fancy power distributors ? Why not make your own ?

I saw a very nice solid aluminum power distributor casing in one of our local electronics surplus stores. It certainly could not be considered as refined, but was made from solid 5 mm thick sheets and had nice cut out holes for US sockets and an IEC inlet.

Choose your favourite sockets and your internal cabling of choice, and you are ready to go.

In my case, I used the following :-

1 x Oyaide SWO-XXX AC outlet

1 x Hubbell 8300 Hospital Grade AC outlet

1 x Hubbell 5362i AC outlet

1 x IEGO gold plated IEC inlet

Neotech 12 AWG PC-OCC teflon insulated solid core copper wire

Raw materials before assembly.

Fit and finish is a bit rough

Close-up of the Iego IEC gold plated inlet. Silver plated o-ring terminals are provided.

You can also put in your choice of damping material, e.g. Fo.q, bitumen sheets. Feel free to put in other stuff like AC line filters (X-rated capacitors only please and make sure that your leads are well insulated !). For the new age guys, put in your crystals of choice.

There you have it – a nice and high quality distributor for not too much money.

Ground wires all terminate on the earth screw of the first AC receptacle

The bent Neotech cables. A good work out ! Getting the right length is absolute critical.

Dry fit

Finished product !

Any practical tips ? If I had another go at this, I would use either multi-stranded copper wire or multiple runs of a smaller gauge wire. The 12 AWG is stiff as hell. Needless to say, please check your wiring for continuity and shorts using a multimeter before connecting it to the mains.

Based on my daisy chain wiring, the first set of receptacles would sound the best. Wiring the receptacles in parallel would have been difficult and probably require me to change to thinner cables to terminate properly at the IEC inlet.

Also, the screws provided on this casing are absolutely useless and deform at the slightest pressure. All screws and hex nuts were changed to stainless steel type.

The outlets of the Hubbell are connected together via a thin metal bridge (to facilitate snap off in case of split voltage wiring needs). I suppose breaking off the metal bridge and using a copper wire would improve the sound a bit.

Total cost if you used Hubbell outlets and Neotech copper wire would be about USD 160. If you were feeling rich, you could use the Oyaide R-1 (which I use in an Oyaide MTB-6 used in my main system) and solid silver wiring.

Happy DIYing ! An important disclaimer, if you have no idea what you are doing, please buy a commercial product. We are dealing with lethal voltages here.

6SN7 Comparisons

2011-02-06T21:39:00.000-08:00

Here are some listening notes from experimenting with a variety of 6SN7 tubes in my Cary SLI-80 integrated amp (used as a driver).

Tungsol GTB re-issue

These tubes are really quite good. After chalking some hours under their belt, these tubes have good handling on both bass and treble extension and have a smooth and liquid midrange. I find the Tungsol to be a wee bit less transparent than the EH, but the Tungsol has the heft and liquidity that could be said to be more musical. Dynamics in particular are superior on the Tungsol. Instruments and voices also tend to have more tonal density and bigger image size compared to the EH.

Electroharmonix

Visually, the internals of the EH tube are almost identical to the Tungsol re-issue. The plates are of a slightly different colour, and the halo getter is larger and the bottom part of the ring is attached to the support rods, compared to the Tungsol where the top part of the ring is attached to the support rods.

Sound wise, both tubes have quite a lot in common but also enough differences to justify choosing one over the other.

Overall, the EH is a little bit lightweight in comparison to the Tungsol. The Tungsol has a firmer and meatier bass and a thicker midrange. The EH has a good shimmery top end. Instruments are well separated but are a bit lacking in height and depth.

To sum it up, the Tungsol has a more romantic balance, while the EH has a more modern and analytical feel to it.

General Electric GTA D getter

This tube has the strongest feeling of “being there”. The sense of acoustic space and the 3D soundstage projected are its strong points. Its weakest point is an overall lack of bass weight, and an energetic top end that seems to emphasize sibilance and get lost in complex mixes. Its strong points warrant it serious consideration but in the end I preferred the more even handed presentation from the RCA and Tungsol.

RCA GTB Black Plate

The RCAs project good acoustic space and strike me as being a better behaved version of the GE. Its bass is not as impactful as the Tungsol but has better weight and extension compared to the GE. It has a denser and creamier midrange than the GE and more organized and controlled highs. It is not quite as holographic or transparent as the GE but is more balanced in its approach.

Cary labeled 6SN7

These tubes came as stock in my Cary. I am not too sure who manufactured them but looking at their construction, they look quite similar to Shuguang tubes.

This is a very soft and gentle sounding tube, with a rounded bass that tends to diminish the impact and dynamics of the music. It has a very smooth midrange that is thick and creamy. It is not really a bad sounding tube, but tends to convey music in a warm and syrupy kind of way. It has a reasonably open top end that is well behaved. Well suited for taming a bright system, but it’s a bit too heavy handed for my taste.

Conclusion

My two favourites of this test group are the RCA Black Plates and the Tungsol Re-issue. The Tungsol in particular is affordable, widely available and a decent alternative to NOS / used vintage tubes that are becoming increasingly difficult to obtain cheaply, especially in Asia. The Electro Harmonix should not be written off and should be considered if a leaner and brighter presentation is preferred.

Telos Audio Design RCA Caps

2010-11-20T06:37:00.000-08:00

Telos Audio Design (http://www.telos-audio.com.tw/) was almost unknown in Singapore until recent distribution by local distributor, Audio Basic. Telos has beautiful and well made RCA caps. The interesting thing is the manufacturer's claim of sonic benefits from using these RCA caps to cover unused inputs and outputs. Bear in mind that their caps are of non-shorting design, i.e. there is no shunt of positive to ground.

Telos caps are made of copper and then plated in either gold or platinum. Fit and finish is excellent and is as good as jewelry grade. Insulation is teflon.

Photos from official website

I have had a set of both the gold and platinum caps for some time now but did not quite get around to writing a post on them. Part of the reason is my difficulty in rationalizing why these caps work so well. The manufacturer claims that they protect equipment from stray EMI and RFI. I think the reason is far more complex than suggested.

Both caps have a not so subtle effect. Putting on just a single pair of caps on an unused input lifted the haze that made the system sound homogeneous and blurred. Vocals in particular focussed tightly and instruments became more distinct and in sharper contrast to the background.

The platinum caps were the most dramatic of the two. Vocals actually became slightly more distant but with increased focus and texture. Micro-detail was excellent and the extension of high frequencies, especially hi-hats was particularly impressive. I noticed that the platinum caps tended to accentuate the sense of acoustic space in the recording.

The gold caps in comparison presented vocals in a more forward manner, but with a touch of warmth and smoothness. High frequencies also were more extended but to a lesser degree compared to the platinum caps. Bass notes gained both substance and extension, something which the platinum caps did not really do. Micro-detail was not as good as the platinum caps though.

How many to use ? And should you combine the platinum and gold together ? This is one situation in which you really need to experiment. Here are some observations I notice during my experimentation with these caps,

- The input being covered matters. If you have say three unused inputs, using just a pair of caps on each of those inputs will yield different results.

- Don't just try inputs but also outputs. You can even try covering the coaxial output of your CD player / DAC.

- You can combine them to get the strengths of both caps. But I preferred using the same type of cap throughout as I felt that the system sounded more coherent that way.

- More is not better. My best results were obtained using just a single pair in any one component. In fact using too many causes the sound to collapse and sound shut-in, sounding even worse than stock !

- Although the platinum caps are potent, they can make vocals too sharp and sibilant, especially if you use more than one pair per component.

At their low cost, Telos caps are a must have. I bought a box of the platinum and gold caps, and probably have enough caps to tune 3 or 4 systems.

Almarro A-318B SET Tube Amplifier - Photo Essay and Mini Review

2010-10-30T03:51:00.000-07:00

Photo Essay

Beautiful and classic workmanship. 18 watts of single ended power. Tube complement - 6SL7, 6SN7, 6C33C.

8 Ohm and 4 Ohm speaker taps, 3 inputs and an IEC inlet with user accessible fuse holder.

Russian 6C33C double triode. From Soviet era missile and Mig Foxbat service to consumer audio. How the world has changed !

Volume control.

Carved logo on the front panel.

Input selector. There are 3 inputs. The first indent is mute.

RCA 6SN7 GTB and Sylvania JAN VT-229 tubes

Power transformer is inside the chassis. The exposed center "transformer" in the first photo is in fact a power supply choke.

Russian K42-Y2 coupling caps. A surprise, quite uncommon in commercial gear.

Mini-Review

The Almarro A-318B is quite an unusual beast. Single-ended triode and assembled by hand in Japan, the A-318B is affordable, beautiful and powerful - typically these words are not seen together in the same sentence.

Being an integrated amplifier, you save quite a bit of useful money. Total up the cost of a preamp, with an additional power cord, a pair of interconnects, footers, etc, and you realise that the savings are not insubstantial.

Despite its compact proportions, this is quite a heavy amplifier, tipping the scales at close to 20 kg. Much of this weight comes from its massive power and output transformers. The next thing that hits you is the sheer amount of heat produced, not just from the very hot running 6C33 power tubes, but from inside the chassis. An hour or two of operation even in an air-conditioned room will guarantee you a nice and toasty top plate and volume knob.

Operation is generally fuss-free and uneventful except for two things. First, the bias tabs (sitting underneath the tube socket base) may be accessed by itchy fingers - owners with children please take note ! The position of the two tabs are dangerously close to the top plate and accidental contact is not only possible but very likely, especially if you have a habit of biasing your amp in your dimly lit man-cave, after a beer ot two. It is far safer to take the bias from the two metal screws directly above the tabs on the ceramic tube scoket base. Secondly, I had intermittent contact with one of my power tubes. This traced back to a slightly loose tube socket. My amp is about 3 years old and was bought pre-owned. Anyway, I re-tightened the sockets with insulated needle nose pliers (you have to turn the amplifier over and take off the bottom plate to do this) and did not have any further incidents.

Right off the bat, it is obvious that the Almarro has more drive than its low power suggests (18 watts SET, but my set was delivering probably close to 15 watts at maximum due to my choice of a slightly lower bias point).

In the lower frequencies, the Almarro is no shrinking violet and has enough grunt and slam when driving my Focal Micro Utopia BE speakers (90db sensitivity, 8 Ohm load). The bass is not the most extended or deep (leave that to my Class D amps) but has sufficient heft and articulation. That being said, the Cary SLI-80 has deeper and more powerful bass.

Coming to the midrange, this is probably where the Almarro defines itself. Vocals have a beautiful glow and are open and realistic. Brass instruments and strings are equally well portrayed, with more emphasis on tone and acoustic space.

High frequencies are similarly open with cymbals shimmering in the right way with correct emphasis on both the transient and the decay.

The Almarro is a beautiful amp designed to appeal to the emotional side of things. From the logic side, the Almarro does not have the best of extension at both frequency extremes. It is easily bettered by the Cary SLI-80 in this respect. Resolution is good but not world class. Soundstaging, imaging and separation are acceptable to slightly above average. Despite all this, the listener is too busy listening to the beauty of the Almarro's tone to notice or care about such things. The feeling of holographically "being there" is a strength of this amp How the Almarro manages this without being a champ in imaging and soundstaging is baffling !

Asking my partner for a second opinion, she concluded that the Almarro was beautiful but somewhat emotionally draining, while the Cary was more balanced. I reckoned that this has more to the do with the high level of emotional engagement of the Almarro.

If you are the sort of listener that wants to be able to feel the emotion of a violin concerto instead of being able to discern the exact placement of all performers of the stage, bowing technique, what they had for lunch, etc, the Almarro is definitely for you. As long as used sensibly with speakers of suitable ease of drive, the Almarro is able to deliver a slice of high-end at real world prices.

Audio-Gd DAC19 DSP

2010-10-18T22:23:00.000-07:00

Talk about quick shipping ! My order with Audio-Gd has been pending for quite some time now as I wanted some customised inputs done (gave up the USB input to convert to another coaxial input). It was shipped out on Saturday afternoon and arrived in Singapore at my doorstep on Monday evening.

The order process was hassle free and the unit was well packed and arrived in good shape.

The DAC19 is based on two Burr Brown PCM1704UK DAC chips paired with Audio-Gd's proprietary DSP filter. Audio-Gd's principal, Mr. He Qinghua has made an announcement that he is discontinuing his products based on the PCM1704UK due to difficulties in obtaining supply of the chip. That was enough reason for me to take the plunge.

You can refer to http://www.audio-gd.com/Pro/dac/DAC19/DAC19EN.htm for full technical details.

The DAC-19 in finished in a shoe-box sized case that is rather utilitarian. The case is decently finished and will not win any prizes for either fit or finish. Given its asking price and performance, this is acceptable to me. I can do without paying a lot more for a snazzier case that does nothing for performance. There is a little bit of free play on the front selector switch, but otherwise, the rest of the switches and jacks are functional and do the job.

It has been suggested elsewhere that the DAC-19 is not particularly sensitive to quality of transport, digital cables etc, or power cables, by reason of its powerful jitter reduction and power supply quality respectively. I believe that it is wrong to disregard those factors and use of the DAC-19 over the short time I have had it suggests that strong dividends may be reaped by paying careful attention.

Transport duties were handled by Slimdevices Squeezebox 3, linked with Oyaide's DB-510 digital cable. Out of the box, the DAC-19 sounds detailed and resolving in the midrange and high-frequencies, albeit sounding a bit bleached and light weight. Bass in particular is not deep or impactful and the overall balance is a bit dry. Things changes drastically after extended burn in, with vast differences heard past the 50 hour mark and 200 hour mark. New owners who suffer from buyer's remorse upon hearing the DAC-19 would be well served to persist in their burn-in duties and not give up !

Once well cooked, things become a bit interesting. Both the top and bottom end of the DAC-19 open up and you get tight tuneful bass, as well as extended and airy highs. What you do not get is any form of euphony or colour in its presentation.

Comparing the DAC-19 to my Lite DAC-50 was an academic lesson in extremes. First off, my Lite DAC-50 is quite extensively modded, with changes in the power supply as well as some circuit modifications in its tube output stage and coupling caps. Once modded, the Lite is rich, organic while sounding open and dynamic. It would be considered by most to be a musical sounding DAC. It also has a strong sonic signature and its richness of tone as well as its weighty and deep bass are obvious in all recordings.

The DAC-19 sounds neutral, rich or lean, depending on the recording. It seems truer to the recording than most, and as such will not help systems that are deficient in certain areas. As such, the DAC-19 would work best in systems that are already well-tuned for a neutral source. Paired with the Acrolink 4020-7N power cord, the DAC-19 sounded a bit bright and thin. Changing the power cord to Acrolink's factory terminated 4030 power cord fixed this..

Similarly, a bit of tuning was needed in respect of the footers supporting the DAC-19. A trio of Finite Element's Ceraballs made the sound too forward. Replacing that with Golden Sound's DH cones struck the best balance between cleaning up the sound and adding some weight to the presentation of the DAC-19.

Describing the DAC-19's sound is more difficult than most equipment, because it does not seem to have any intrinsic sonic signature of its own.However, after extended listening, the one striking quality of the DAC-19 is its ability to resolve and present instruments and voices in the most complex of mixes in a coherent, well placed and separated manner. The Lite DAC has a tendency to spotlight the main vocals and principal accompanying instrument, with the other instruments relatively obscured. The DAC-19 resolves both well, with a surprising amount of low level detail that is not immediately apparent on other equipment.

For it's asking price, resolution of this nature is class leading. I am quite sure that a DAC of this quality with a Western manufacturer badge and snazzier case could easy cost 3 times as much as the Audio-Gd. If you are looking for a DAC that digs deep into your recordings and presents a true picture of what's there, you would be well advised to check out the DAC-19.

Pictures from Audio-Gd's official web-site

Capacitor shoot out

2010-09-08T22:17:00.000-07:00

Oh No ! Not another capacitor comparison test !

Actually, no one likes comparing capacitors. Do we really have nothing better to do in life but to swap capacitors in an out of circuit, burning in numerous capacitors just to find out how they sound ?

Right now, the stock Wima MKP10 output coupling caps in my Diva Audio M7 have been taken out and the wires soldered to alligator clips instead, to facilitate ease of swapping the caps in and out.

Unlike some testers than undergo thorough and scientific methodology, there was no blind testing, or gruelling 500 hours burn in test. Neither are all caps of identical value because many of these caps just happen to be lying around for trial. But according to my calculations, all of the capacitors tested are large enough in value to not cause any audible degradation to the bass response in my system.

All caps will get at least 10 hours of burn in time and at least a few more hours of casual / serious listening. Ocassionally, I will go back to the Wima as a sanity check.

The line-up (in no particular order) :-

1. Clarity Cap ESA
2. Solen Fast Cap
3. Auricap
4. Obbligato Gold Premium Cap
5. Jantzen Superior Z Cap
6. Mundorf M-Cap
7. Mundorf Supreme
8. Mundorf Supreme Silver in Oil
9. Mundorf Supreme Silver / Gold
10. Ampohm Paper-in-oil Tin Foil

(Top Row, Left - Right, Solen, Obbligato, Clarity Cap, Auricap, Mundorf M-Cap)
(Bottom Row - Left - Right, Jantzen, Wima, Mundorf Supreme, Mundorf Silver / Gold, Mundorf Silver in Oil)

For a value reference, here are the online prices of the above caps for 1.0 uF in USD arranged in order from the cheapest to the most expensive.

Solen                                               $1.76
Mundorf M-Cap                              $3.54
Wima MKP10                                 $4.00
Clarify Cap ESA                              $8.90
Obbligato Gold Premium                $10.50
Jantzen Superior Z Cap                  $12.00
Mundorf Supreme                          $20.00
Auricap                                          $21.50
Ampohm Paper-in-oil Tin Foil        $29.95
Mundorf Supreme Silver / Oil       $48.00
Mundorf Supreme Silver / Gold     $68.00

Stock Cap - Wima MKP10

Absolutely nothing wrong with the Wima. The MKP10 is a common sight in quite a lot of expensive equipment and instantly recognisable by its red rectangular box appearance. I know that T.S. Lim of Diva Audio favours this cap for its neutrality and dynamics.

It is a neutral cap and in the wrong systems can sound a bit lean. It is quite open and gives the impression of an overall lack of euphony or bloom. Although it has a relatively smooth midrange, when things get busy, the midrange can take on a bit of glare and hardness. In such situations, the treble becomes a bit tizzy and messy. This was made very obvious when going back to the Wima from the Mundorf Silver / Gold.

In terms of soundstage depth and presentation, the Wima is like sitting close to front row. Mundorf capacitors in comparison are more like sitting in the middle row.

Clarity Cap ESA

A very pretty cap and its metal foil body looks impressive. Initial impressions are that of a very dark capacitor with recessed midrange and not much treble extension. Thankfully, after a few hours of burn in, things improve quite lot.

This is an interesting capacitor. It has a weighty mid-bass that gives lower piano notes good solidity and feel. Vocals sound inviting and smooth, with almost no trace of sibilance on the usual problem tracks. Further listening reveals that the midrange is recessed and slightly less resolving as the Wima MKP10. Unlike the Wima MKP10 that has a dry and honest treble, the ESA has an airy treble and high frequency sparkle that highlights the decay of cymbals and high hats, and "enhances" the sense of acoustic space in recordings.

This could be an ideal cap to tame overly bright and lighweight sounding systems without making the overall presentation too dark. Given its relatively modest price by high end cap prices, this cap has plenty going for it.

Auricap

Auricaps come is a nice bright yellow wrapper and have insulated multi-stranded leads, one of which is black and the other red, presumably to differentiate the outer foil of the windings from the inner foil.

Audience, the manufacturer of Auricap, recommends that the signal enter through the black lead and exit through the red lead for signal coupling purposes, which is the way I installed them.

Moving from the Clarity Cap ESA to the Auricap restored my system back to the same tonal balance as the stock caps - neutral. Don't make hasty conclusions about this cap. For the first two hours, although it sounded neutral, high frequencies had a strange wobbly quality, a bit like tape speed variation. After about five hours, this more or less disappeared.

Compared to the Wima, the Auricap has a smoother midrange but a neutral balance through the whole audio frequency spectrum. The ESA has more air and high frequency sparkle than the Auricap. You can say that the Auricap does nothing wrong, but look elsewhere if you are looking for a cap to colour the tonal balance of your system.

Mundorf Supreme

The Mundorf Supreme is the bottom of the Supreme range and is physically huge for its rated value. This is probably some part due to its induction free design which effectively uses two capacitors in series within the same casing. Do check the space available in your casing before you buy !

The Supreme ended up with a little more burn in than usual due to a strange phenomenon. The first few hours were fantastic ! Smooth, liquid and the most beautiful and lingering decay from notes. Things then took a turn for the worse, with the caps entering into a decisively unhappy state - the midrange in particular was hashy and grainy.

Way past the 10 hours mark, things began to settle down and serious listening could commence.

Coming from the Auricap, the Supreme was on the other side of the fence, highly musical, entertaining and perhaps not the most accurate sounding of capacitors. Although the tonal balance is quite neutral, the Supreme has a very polished and refined midrange with the right amount of meat throughout the frequency range. Musical notes are presented with texture and fine nuances, making the Auricap sound dry in comparison.

Easily the most pleasing of the caps tested this far, the Supreme combines the weight and treble extension of the Claritycap ESA with the speed of the Wima MKP10. Coupled to its highly resolving and musical nature and affordable price, do consider the Supreme for your next purchase. To nitpick, the only criticism against the Supreme against its competitors so far would be a slight loss of resolution in extreme high frequencies, and its artistic rather than honest approach towards music. The latter point is subjective anyway and you may personally have a preference for this.

Mundorf Silver/Gold

The Mundorf Silver/Gold sounds remarkably like the Supreme. What does spending 3 x more get you ? Highs are more extended with a better sense of air and resolution. Midrange has a warmer glow to it. Overall this cap sounds slightly more liquid, a bit like how the Supreme sounds initially (the subject cap here is very well run in since it is on loan from a friend who has put considerable hours on it) However, despite the subjective improvements, the value proposition is hard to argue. If funds are unlimited, this is a moot point. But if you have a choice between choosing the Supreme for 3 critical locations, compared to using the Silver/Gold for just one critical location, I would choose the former without hesitation.

Mundorf M-Cap

Compared to the Wima, the M-Cap sounds softer and more rounded. As a result, dynamics suffer a bit, with bass notes lacking in impact and extension. The Wima sounds a lot more open in comparison although the M-Cap does have a pleasingly smooth midrange. Unfortunately, the M-Cap sounds smooth yet has a sibilance problem in the midrange. In the upper frequencies, this cap sounds dry and restricted. The treble also has a tendency to get splashy when things get busy. The only conclusion I have is that this cap is probably more suited for some other application and is not suited for high voltage coupling use. This is the only cap so far in listening tests that make you want to reach for the power switch !

Mundorf Supreme Silver / Oil

What a breath of fresh air ! Coming from the M-Cap, the Mundorf Supreme Silver in Oil is a treat for the ears. The Mundorf Supreme family of capacitors have a distinct family sound. The Silver in Oil is much more liquid and open compared to the Supreme. I actually prefer this to the Silver / Gold. The Silver in Oil is very extended at both ends with excellent microdetails in the midrange and high frequencies. It is also exquisitely refined with an excellent balance struck between being analytical and musical. It lacks the midrange glow of the Silver / Gold but is more even throughout the entire frequency band. At all times, it sounds effortless and natural. Strongly recommended !

Obbligato Gold Premium Cap

Initial impressions during burn in time were quite promising. A very even handed performer with a neutral balance and good detail throughout. Balance wise, this reminds me of the Auricap the most except that the Obbligato has more extended and wetter highs. Midrange is pleasingly smooth without being muffled and there is plenty of information being conveyed in a tidy and controlled fashion. The Achilles' heel of this cap is its bass which is slightly rounded and not particularly deep, especially compared to the Mundorf Supreme series. This results in a somewhat lighweight sounding presentation. That being said, this is a very good cap, especially considering its competitive price. Subjectively, I feel that except for the bass issue, the Obbligato is more pleasing than the Auricap at a much cheaper price.

Jantzen Superior Z-Cap

The Jantzen Superior Z-Cap struck me as being remarkably similar to the Obbligato except for two material differences. Firstly, the Jantzen has a more extended and prominent bass, and high frequencies are fractionally more open and extended. With outstanding neutrality from top to bottom at a modest price, this is a very good cap with excellent price to performance ratio. From a subjective point of view, I prefer this slightly over the Obbligato. If the Obbligato could be said to be a wee bit off neutral towards the warm side, the Jantzen is a wee bit off neutral towards the cool side. My usual comment on neutrality applies, the Jantzen communicates the signal with an even hand - look elsewhere if you are looking for added “spice”.

Solen Fast Cap

According to common Audiophile wisdom, using a cap like Solen in signal carrying duties earns you a one way ticket to the Audiophile Hall-of-Shame. Well, surprise-surprise. Maybe using Solen caps is not the Audiophile faux-pas it is made out to be. The Solen can best be described as inoffensive but not particularly inspiring. On the plus side, it is smooth and pleasant. You can listen to it and fall asleep. Comparisons to the other caps show that the Solen looses some low level information, with high frequency air and information being most obviously affected. The overall outcome is not life threatening and Solen would probably do fine for limited budget projects. In the test set-up, it fared better than the Mundorf M-Cap. Sonically, its second from the bottom of all the caps here on test. To put things in perspective, given its almost giveaway cost, you could do a lot worse.

Ampohm Paper-in-Oil Tin Foil

Words cannot describe how big this capacitor is. I was filled with pride when my package arrived from the distributor of Ampohm, www.audiocap.co.uk (great buying experience - try them !). I excitedly showed my partner the oil filled capacitors that looked more like a smoke grenade. Don't even think of using them in tight spaces.

Ampohm capacitor with a Solen cap of the same value for comparison.
You didn't think I was joking about the size did you ?

The Ampohm sounds quite good. Good enough to fall nearly at the top of the heap. Taking into account its relatively affordable price, this is quite an achievement. Unlike vintage paper-in-oil caps or some other current production brands, the Ampohm manages to sound rich, liquid and extended at the same time. Its tonal balance is similar to the Mundorf Silver / Oil or Mundorf Silver / Gold. If compared side-by-side, the Ampohm sounds "blacker" with very silent quiet passages. Initially, there is an impression that instruments like cymbals and high-hats have less detail and decay. However, after extended evaluation comes the realisation that such instruments are equally detailed and extended but put in less stark contrast compared to the Mundorf Silver / Oil. Value for money wise, the Ampohm definitely beats the Mundorf hands down. Although I still prefer the Silver / Oil, I can imagine that the Ampohm could suit other systems better. Highly recommended !

Conclusions

Despite having personal preferences, it is worth stating that most of these capacitors would do perfectly well in all but the most critical applications. My favourites at the end of this test are :-

Cost-no-object - Mundorf Supreme Silver / Oil. Close runner-up, Ampohm Paper-in-oil Tin Foil.
Best of the rest - Jantzen Superior Z-Cap, Mundorf Supreme, Obbligato Premium Gold

For the selection of the best of the rest, it is a bit like baby bear's porridge - the choice of "just right" depends on your system. Jantzen if your system needs a wee bit opening up. Obbligato if your system is just right. Between these 3 caps, the Mundorf is for the heart (emotionally expressive) while the Obbligato and Jantzen are for the mind (neutral and truer to source).

Virtue Audio M5001 Monoblock amplifier

2010-08-24T22:28:00.000-07:00

Virtue Audio is the new kid on the block in terms of manufacturers offering ICEpower based products.

ICEpower is by now quite established and there are many companies out there offering amplifiers based on their modules such as Bel Canto Design, Wyred4sound etc.

I normally do not write detailed reviews but was suitably motivated by the M5001 which avoids being a “me too” product by virtue (no pun intended) of its tube buffer supplied by Dodd Audio.

The M5001 is based on the ICEpower ASP500 module, which delivers 250 watts per channel into 8 Ohms and double the power into a 4 Ohm load. The ASP500 module includes a built in switching power supply and accordingly runs cool and efficiently.

The stock module input impedance is raised from 8 kohm to 100 kohm due to the tube buffer. This presents a much easier load for preamplifiers to drive, in particular tube based designs.

Appearance wise, the M5001 is quite handsome with a well finished case and lovely real wood veneer top. A variety of finishing options are available to customize the look of your amplifier. Round the back, an IEC power socket accepts detachable power cords, and input is via either an RCA or XLR balanced socket. A subwoofer output is provided.

The speaker binding posts deserve a special mention. The propeller posts make finger tightening a breeze. Both the binding posts and RCA socket are said to be made from gold plated Terrilium copper.

It is not quite the epitome of hi-fi bling-bling, but is certainly well finished enough to be proudly displayed on your equipment rack.

(Pictures from Virtue Audio's official web-site)
Dimensions are not quite shoe box like, with the width of the amplifiers being about 10 inches across. This makes placing each monoblock side by side a bit tricky for most equipment racks as you will find that the support columns will either block the AC inlet on the left of the unit or the input jacks on the right. The supplied feet are metal discs that screw into the chassis. As they project out of the chassis footprint, this makes each monoblock occupy a fair amount of real estate. The feet are easily removed though if you so wish.

Let us re-visit my impressions of ICEpower over the years :- extremely tight and powerful bass, high resolution and detailed midrange and treble, effortless presentation. The downside ? Dry midrange, lack of treble air and 2D like image.

After about 15 hours of burn in, and with the stock JJ 12AX7/ECC83 tube installed, serious listening sessions were conducted.

Preamplifier duties were handled by Diva Audio’s tube based M7. My M7 utilises a tube rectified and choke loaded power supply and has been upgraded to the latest specification by T.S. Lim with additional voltage regulators on the power supply and star ground wiring. The M7 can be best described as a linear and fast sounding pre-amp with both speed, dynamics and good bass authority.

After some trial with the speakers available at hand, the M5001 was matched with my main speakers, a Focal Micro Utopia BE.

The first impression was that of absolute control over both frequency extremes. Bass was tight and controlled.

Midrange is neutral with just the slightest hint of fullness.

High frequencies are extended with absolutely no loss of detail.

Resolution, in particular micro-detail is excellent with individual instruments in a mix being discernible even under the heaviest of mixes. One would be even tempted to flog the oft-used and abused audiophile claim of hearing detail in familliar recordings that went previously unnoticed.

The tube buffer would appear to mitigate much of the criticism I had against ICEpower. Images are fleshed out with proper depth while treble air and the sense of acoustic space are delicately conveyed. I did not see any downside from the installed tube buffer since all the things I liked about the stock module remained – no slowness in transients, or loosening of bass grip.

All that being said, this is by no means a tube-like amp. If you want tube liquidity, get a tube amp – this is not going to float your boat. The tube buffer does not honey coat the sound, it imparts a subtle warmth and organic flow to the dry sound of the stock module. Tonal balance wise, it still remains on the right side of neutral.

Choice of tube used in the buffer as well as pre-amp used could go a long way to tuning the sound the way you want. As far as I am aware, the M5001 can be used with most of the 12A*7 family tubes, enabling fairly cheap and flexible tube rolling, since you can avoid the insane pricing in the 12AX7 family and go for cheaper equivalents in less popular families like the 12AT7 for example.

Hyper-detailed and analytical with the subtle touch of liquidity and warmth – coupled with loads of power to control almost any speaker out there on the market. Take into account its relatively modest price, and I think Virtue Audio has an absolute winner on its hands.

Acrolink S-1400II speaker cable

2010-08-21T22:52:00.000-07:00

The Acrolink S-1400II sits about mid-way up in Acrolink's 6N speaker cable range and is a large gauge version of the S-1000II.

Full specifications of the S-1400II can be found at

http://www.acrolink.jp/english/products/6n_s1400_2.html

(Picture from Acrolink web-site)

The S-1400II is a heavy but flexible cable and termination into your plug of choice is not difficult. There isn't much buzz about Acrolink speaker cables compared to their power cords (the 4030 being the most prominent of their line-up) and interconnects to a lesser degree.

If you have a look at my previous forays into the Acrolink family, I have come to a personal conclusion that Acrolink has a house sound - a delicate midrange and a high frequency extension and air that is not sonically neutral but artistically beautiful.

The S-1400II has the same delicate and refined midrange but a harmonically rich and heavy mid-bass and bass. In a complete Acrolink set-up, the combination works very well to add weight to the bottom end of the spectrum (which is not an Acrolink strength) as well as to keep the highs under control. Substituting out the S-1400II for a pair of Clear Day Audio Double Shotgun or a Goertz AG-1 (both cables are co-incidentally pure solid core silver cables) tipped my main system (Focal Micro Utopia BE) into excessive high frequency energy and harshness.

However, using the S-1400II in another darker system was far too much and the overall result was a shut-in sound that had the speed of molasses.

I suppose the difficulty in matching the S-1400II accounts for the number of used pairs up for sale (at steep discounts mind you) on local hi-fi forums. Its' laidback and rich presentation mandates careful deployment. Unlike some other harmonically rich cables like the Canare 2S16 and 4S8 though, the Acrolink is far more transparent and resolving.

I have noticed that when using Acrolink cabling in pre / power set-ups, better results were obtained in my system by using a single Acrolink (A-2070II) between source and preamp, and an Acoustic Zen Silver Ref-II between the preamp and poweramp. This was better compared to using an Acrolink 2400II in place of the Acoustic Zen.

Conclusion - Very nice cable at current low second hand prices, but probably suitable only for full Acrolink setups or in overly forward and bright systems.

Marantz CD6003 modification

2010-07-31T23:13:00.000-07:00

I managed to acquire an almost mint condition pre-owned Marantz CD6003 recently. Brand new, this CD player is priced at a modest SGD 388 in Singapore, pricing it in the mid-entry level category.

Once upon a time, long long ago, a CD player of this build and sonic quality would cost at least two to three times the retail price of the CD6003. It's nice to see that the price of quality kit like this has come down over the years.

The CD6003 is quite a handsome player and has good build and heft (slightly over 5 kg). The chassis is fairly rigid with a double layered bottom plate and compared to the SA8003, the immediate giveaway in cost cutting is an extremely flimsy CD tray.

Based on the Cirrus Logic CS4398 DAC and Marantz's proprietary HDAM SA2 analog output stage, the CD6003 packs fairly advanced technology for a player of its modest price.

An IEC socket permits you to play around with after market AC cords if you wish.

Popping the hood yields no surprises, with three circuit boards connected by ribbon connectors. The left board is the power supply section with two separate power supplies. one linear and the other switched mode.

The center board controls the transport and the right board contains the DAC (hidden on the underside of the board) and analog output stage. The analog output stage is Marantz's HDAM SA2 circuit and is basically a discrete transistor circuit.

There is a lot of information out there on modding Marantz CD players, the most famous being the infamous CD63/67 modification thread on DIYaudio. Limited this time by lack of a service manual, I decided to just do a few tweaks that were easy and bang for the buck. The CD6003 is intended for use in my office and I did not wish to spend too much time or expense in this project. Besides, if I wanted a reference class CD player, I would have bought a better one to begin with.

Over the years in modifying Marantz CD players, the most dramatic difference in my humble opinion comes from upgrading the DC blocking capacitors. So far, the Marantz players I have handled (63, 17MkIII and now the 6003) use a pair of Elna electrolytic caps back to back to make them non polarised. Usually I bypass them completely after determining that there is no DC offset. Unfortunately this time around, DC offset was quite high at 150mv. I don't usually try film capacitors in this location due to space limitations and the high value needed to avoid bass roll off. So, a pair of 6.3V 22 uF Rubycon Blackgate HQ NX non polarised caps were used to replace the existing 4 Elna Silmic caps used. I also usually remove the muting transistors, but decided to leave them alone this time.

Next, came the digital power supply to the CS4398 DAC. The local decoupling cap was changed from a 100 uF Koshin cap to a Sanyo Oscon cap of the same value. The stock circuit bypasses this cap with a small ceramic cap which I left in circuit. I have very good experience with the Oscon in digital power supply decoupling and cathode resistor bypass applications.

I also added some blu tack on the oscillator crystal, the CD transport bridge and the transport frame (not visible in my pictures).

Total cost of the modifications is less than SGD 20.

Extended listening was done to the modded and unmodded player on my main system which consists of Focal Micro Utopia BE speakers driven by the Cary SLI-80 Signature Special Edition. Comparisons were also made with my usual CD player, the CEC TL-51XR.

In stock form, the 6003 is a competent player that punches well above its price class. It's sins are one more of omission. It is a smooth sounding player with decent bass and high frequency sparkle. Its failings in comparison to more accomplished machines are a lack of solidity, and somewhat homogeneous presentation of detail.

Observations made using my regular test tracks :-

1. Eva Cassidy - Fields of Gold : Compared to the CEC, Eva's voice was somewhat vague in imaging. Her accompanying guitar was somewhat lacking in bite and body and blended into the background. There was an obvious lack of retrieval of ambience from the recording - the acoustic space from this track which was recorded live at The Blues Alley was not well conveyed.

2. Patricia Barber - Summer Samba. The percussion work about a minute into the track did not have the shimmer and air of the CEC. The fine detail in the high hats etc were not well separated and sounded somewhat lost in the mix. Piano notes were not realistic as they sounded a bit plasticky and lightweight.

3. Rebecca Pidgeon - Spanish Harlem. The sound of the shakers was quite similar. On the CEC, each shake was distinct and varying in image height and volume.

After modification and about 20 hours of burn in.

1. Eva Cassidy - Fields of Gold : The center vocal image is dead center. There is an overall increase in resolution with each pluck of the guitar being more distinct. Vocals are more distinct and Eva's voice has distinct varying shares of texture.

2. Patricia Barber - Summer Samba. The fine details in the high hats were better separated and the shimmer and air improved. Piano notes become a little more solid and more stable in pitch.

3. Rebecca Pidgeon - Spanish Harlem. The differences in each movement of the shaker was more easily discernible.

In summary, the modifications improved midrange transparency and ambience retrieval. Vocals seemed to benefit the most, with the homogeneous nature of the stock player being significantly improved. Although there was increase in weight and solidity of the upper mid bass, the low bass notes did not seem to be improved by the modifications.

The subjective quality of the player was significantly improved but still quite far from the CEC. In separate listening sessions, the differences were quite liveable, but instant A/B comparisons showed that even modded, the 6003 was no CEC slayer.

Lastly, I tried a trio of Finite Element's Ceraball footers under the 6003. The improvement in quality was shockingly good and at least equal to the cap modifications. If we consider the 6003 in stock form to be about 40 % of the quality of the CEC (not bad if you consider that the CEC is more than 4x the cost of the 6003), the cap mods and Ceraball would bring the 6003 to around 60 % of the quality of the CEC.

Cary Audio SLI-80 Signature Special Edition

2010-07-14T22:09:00.000-07:00

Cary Audio's SLI-80 Signature Special Edition amp is now in the house !

Jaguar blue finish.

Output tubes - KT88, 6550/KT88, EL34, 6CA7. Choose your favourite poison.

Rear socket and trim pots are for bias adjustment

WBT Binding Posts

Also functions as a headamp. The headamp runs through the tube circuit and is not the usual separate opamp circuit

Initial impressions were that of a very powerful sounding amp with good grip on the bass (not always a given with tube amps), but a slightly coarse midrange and moderate resolution. Thankfully, the sound opened up and the coarseness disappeared after a few hours of play time.

It runs even hotter than my Cayin A-88T which tells you something ! Don't even think of placing this in an enclosed cabinet.

Like the Cayin, the SLI-80 is based on a pair of KT-88 power tubes per channel in push pull configuration, with 6DJ8/6922 (the Cayin uses 6SL7 tubes here) input tubes and a 6SN7 phase splitter. The SLI-80 may also use KT-66, 6550 and EL-34 power tubes. Power output using KT-88 tubes is 80 watts per channel in ultralinear mode and 40 watts in triode mode.

The power supply is choke loaded and tube rectified by a pair of 5U4 rectifier tubes.

Noteworthy features include basic remote control, switchable triode / ultralinear mode and a headphone output (run from the tubes and not opamp based).

Stock tubes supplied were EH KT-88 power tubes, EH 5U4GB rectifier tubes and EH 6922 input tubes. The 6SN7 tubes supplied were labelled Cary but internally look exactly like Chinese Shuguang 6SN7 tubes.

The Cary labelled 6SN7 tubes were soft, warm and not particularly open, so they were quickly substituted with EH 6SN7 tubes, which resulted in a fairly bright and fatiguing presentation. The EH 6922 tubes were substituted with NOS Mullard tubes, and the EH KT-88 tubes were replaced by Genalex Gold Lion re-issues. This resulted in a fuller and more liquid presentation.After some experimentation, the EH 6SN7 tubes were replaced with GE 6SN7 GTA vintage tubes.

Driving my Focal Micro Utopia BE speakers, the Cary sounded best in triode mode. Ultralinear had more slam and authority but sounded a bit rough and bright in comparison. Strangely, my Cayin A-88T sounded better with the same speakers in ultralinear mode.

The Cary seems quite hard on the rectifiers, and I experienced arcing more than once when switching the amp on. Some audio forum posts suggests that this is due to excessive capacitance being used immediately after the tube rectifiers, but I won't comment on this since I did not open the amp to check the power supply layout.

I also do not like the stock equipment feet which feel and look like sorbothane feet. In tropical weather, they turn greasy and sticky rapidly, leaving unsightly marks all over your rack.

Sound wise, these problems are rapidly forgotten. This amp sounds wonderful. It is certainly not the most transparent amp around, but it did have just a smidgin more resolving power than the Cayin A-88T it replaced. What is gains over the Cayin is a much bigger presentation in the form of a very expansive soundstage and excellent bass authority (for a tube amp). The Cayin projects a flatter soundstage, with image sizes comparatively smaller.

Compared to my Almarro A-318B, the Cary has a warmer and thicker midrange and more extension and air in the high frequencies.

Tone is also more forgiving, with a more liquid and easy going presentation, without sounding dark or shut-in. In comparison, Cayin amps have a more solid state like sound, and may even be argued to be more neutral. If you prefer a slight rose-tinted glow to the midrange and the "wet"type of highs, look at the Cary first !

Acoustic Treatment

2010-06-23T22:37:00.001-07:00

The listening environment is one of the most important "components" in the hi-fi chain that is often overlooked. How a speaker interacts with the room it is placed in will have a dramatic effect on how it sounds to the listener.

In space scarce Singapore, most of us (except for the really lucky / well-heeled ones amongst us) have to make do with placing our audio setup in either the living room or a fairly small spare bedroom.

The typical public housing flat bedroom in Singapore measures about 3 x 4 meters. This necessitates keeping the system small, choosing speakers that do not acoustically overload the room, or resorting to room treatment methods, or a combination of all of the foregoing.

Why does the typical audiophile neglect room treatment ? Laziness ? Cosmetic issues ? Possible irate spousal response ?

Anyway, I have just revamped my listening room and taken the opportunity to acoustically treat my listening room. Unlike American homes, walls in Singapore are almost always built from brick, concrete and plaster. This results in hard reflections and a bit of bass boom.

Room treatment options in Singapore are quite scarce. Professional products are expensive due to the economic inefficiency of shipping large heavy items from American and European audio manufacturers.

DIY is an option, but lack of a garage makes construction a bit tricky. Materials such as wood and rockwool are available but require a bit of effort to track down and transport.

In consultation with Joamonte (resident acoustic treatment expert - you will find him on Singapore hi-fi forums like Echoloft (gone with the wind) and Xtremeplace, treatment was only done on one side of the room, directly behind the system. The treatment consisted of a combination of diffusor and absorption panels.

According to Joamonte, treatment of all the early reflection points could result in the system sounding too dead.

Acoustically, my listening room is not particularly troublesome. It is modest sized (about 3 x 3.5 meters), and has a fairly high ceiling. It is a regular rectangle shaped room, but is acoustically not fully closed on one end, as the wall is made out of plasterboard.

Nevertheless, the room is a little live sounding, and imaging and staging is not as sharp as it should be.

A total of 8 diffusor panels and 2 absorption panels were deployed. The two absorption panels were placed in the corner of the room, at ear level. The diffusor panels consisted of both an early model sold by Joamonte and his current production, which utilises plastic wells placed in a frame. Not much low bass treatment was required as my system does not go very low, probably no lower than 40 Hz.

Verdict :- Great stuff. Soundstaging and imaging are much improved. The tonal balance of the system was not affected much. Some of the obvious improvements were,

Midrange, especially female vocals – female voices were less sibilant and the level of grain was reduced.

Background – much quieter, with very low level detail retrieval becoming much more obvious. Most importantly, the lowering of background noise did not affect the “air” of the system.

Air / Ambience – The sense of air around instruments, and the fade / decay from the initial transient note of percussion and brass instruments were more prominent and longer. This seemed odd as I would have thought that acoustic treatment could have the unwanted effect of reducing this.

The panels were made by a carpenter to Joamonte’s specifications. He has also made some measurements of the room to demonstrate the difference between the treated and untreated room.

It is amazing how spending a relatively modest amount (S$1,600) could change and improve the system tremendously. Instead of spending money on expensive cables and footers, perhaps some attention should be paid to acoustic treatment.

Here are the measurements of the room with and without treatment.

An update much overdue

2010-06-21T22:47:00.000-07:00

Rather unfortunately, it has been ages since I have last updated this blog. There have been lots of changes to my system and lots of new accessories to be covered. Stay tuned for updates on acoustic treatment, the Acoustic Zen Silver Reference II interconnect, Telos RCA caps and speaker post plugs, and much more !

Yet another afternoon of messing around

2009-10-16T03:45:00.001-07:00

Last weekend, I had one of my hi-fi mates over for some listening. He was interested to see how my Thiel CS 1.6 was faring in my system, as well as how it matched with the various amplifiers I had on hand.

For those of you know who are not familiar with the Thiel CS 1.6, it is the smallest floorstanding model in Thiel's range. As a matter of line up, it is actually the replacement of the CS 1.5. Ultra compact models like the 0.5 do not have a direct successor model.

A typical Thiel design, it is designed to be phase coherent as well as time aligned (provided you sit at least 8 feet from the speaker). It is a two way speaker, sporting all metal drive units. Unlike older Thiel models, the CS 1.6 uses in-house produced drivers. Instead of using a conventional rouind port, the CS 1.6 utilises a long thin slotted port in front.

Here are our observations of the day :-

1. Matched with Diva M7 preamp and Cayin A-88T

Sound is quite full with a very nice tube bloom. Bass is weighty but slightly rounded. Transparency is quite good and this combination can entertain for hours, especially if you are into vocal and jazz discs

2. Matched with Diva M7 preamp and Hypex UCD400

Extremely fast sound with much tighter grip over the bottom end. Extremely detailed top end and the resolution is just incredible. The tube bloom is still there with just a hint of sweetness. Hi-fi mate declared this at the end of the session as the best sound of the day.

3. Matched with Copland CTA-401 integrated tube amp

My ageing Copland is one of the first few quality kit that I could afford. Taking me almost a year to save up for, I keep my Copland more for sentimental reasons than anything else.

Paired with the excellent Electro Harmonix 6CA7 tubes, the Copland puts out about 35 watts per channel in ultralinear mode. This is slightly less than the 45-50 watts put out by the Cayin A-88T which is based on KT88 tubes.

The Copland is noticeably slower and rounder than the Cayin. The Copland is an old school type of tube amp in that it provides a very liquid and luscious presentation. The Cayin is much faster and neutral in its midrange and top end in comparison.

Matched with the Thiel, I felt that the overall combination was a little bit too slow and did not highlight the strengths of the CS 1.6 well. Some may like its very romantic and rose tinted view of the world, but its sweetness does not match well with faster paced music.

4. Matched with Kingrex T-20U integrated T-amp

Hi-fi mate had to suspend dis-belief for a moment. Absolutely shocked at the volume that was achievable with the limited power on tap, he though the sound was overall quite good, especially considering the price. Overall, the combination is quite pleasant to listen to but is obviously not as resolving or controlled as the other two combinations above.

Combination 2 was heard with both my new Acoustic Zen Hologram II speaker cables and my existing Goertz AG-1 pure silver speaker cables. It was almost like a night and day difference in presentation. He found the Goertz forward and quite forceful in the way it "projected sound" (in his words), compared to the very gentle and refined presentation of the Acoustic Zen. He prepared the Acoustic Zen's presentation.

For some entertainment, we also hooked up the Kingrex to an old pair of Proac Tablette 50s. Obviously not quite as detailed as the Thiel, the combination was quite very enjoyable. Always musical, the Proac entertained well with its PRAT and sharp imaging ability.

Sadly, the session was so much fun that it ended far too soon. You can be sure that another session will be arranged soon.

Acoustic Zen Hologram II Speaker Cables

2009-10-06T22:49:00.000-07:00

(Picture from official web site of Acoustic Zen)

Bought pre-owned from Audiogon, my new set of snakes arrived last month. After going through a overland trip from Florida to Oregon before being shipped by air to Singapore, these snakes are more well traveled than I am.

The AZ Hologram is a big thick cable finished in a handsome purple cover with light reflective mesh (so that it can remind me of its presence in my fairly dark listening room ?). My pair is finished in PCOCC gold plated copper spades on both ends with the speaker end split for bi-wiring.

The AZ is fairly flexible and despite its bulk, is quite tame and refrains from trying to pull equipment or speakers down from their perches. Wish I could say the same for the horrendously heavy PAD cables I have lying around somewhere.

Given its very heavy gauge, I was expecting the AZ to have a thick and heavy sound with bone crushing bass …… not. After a brief run-in, listening tests show that this cable is actually quite balanced but with a few strange characteristics that took me by surprise.

The first thing you notice is a perceived “drop” in loudness. The second is the rather distant presentation, almost as if you have been moved back from the front row to the mid section of the concert hall.

After some adjustment of the ears, you realize that the cable is extremely quiet. The apparent reduction in volume is a result of the bass which is tight but not particularly extended, and the high frequencies that are all there, but do not jump out at you. Extended listening reveals that the cable is very detailed with excellent low level resolution and microdetail. This is all very apparent due to a lack of grunge, sibilance and glare in the high frequencies. This enables the cable to sound smooth and non-fatiguing without throwing away detail.

Bass lines are neither thunderous nor weighty. In fact, the bass is extremely tight, but does not appear to go down deep. Coupled with the very refined high frequencies, this makes for an extremely refined and civilized cable that is well balanced from the bottom end to the top end.

Maybe as a result of its distant presentation, soundstage depth is incredible and deeper than anything else I have ever tried.

In comparison to the Goertz AG-1 cable that preceded the AZ, the AZ has very defined and clearly delineated image spaces. The Goertz has what local audiophiles term as “big-mouth” sound … ask a Cai Qin fan and he will know exactly how this sounds like. The Goertz has an extremely detailed feel to it, and much like the Acrolink cables I covered in an earlier post, the Goertz takes a health dose of artistic licence to texture the tone of instruments and the human voice. In contrast, the AZ is truthful and reflects the picture as it is.

The AZ is such a clean and balanced cable, that you wonder what the fuss is about. After taking the time to know it better, you realize that it communicates loads of detail in a coherent and balanced manner, without sounding harsh or introducing glare. All in all, this is a worth contender for systems that can showcase this cable (price wise, its definitely destined for entry level high end systems at the minimum).

Speaker filter

2009-09-21T09:03:00.000-07:00

Here are some pictures of my DIY speaker filter inspired by several threads on Audioasylum.

Very much like the Combak Enacom or the Walker High Definition Links, these are R-C networks or zobel networks that are applied in parallel across the speaker or the amplifer if you prefer (although they usually work better across speakers).

They will filter out ultrasonic garbage that happens to be in your system and their efficacy across the band depends on the value of capacitor and resistor that you use.

Why this project ? More out of necessity rather than vanity. The Alpha-Core Goertz speaker cables I use have much higher capacitance than average, enough to upset some amplifiers into oscillation. I thought I heard my AG1 speaker cables induce a hazy grain on the top end of my Hypex amplifier the other day. Maybe it was my imagination, but it was frightening enough to get this project up pronto. Zobel networks, besides their filtering effect also stabilises amplifiers.

Since this is a prototype project, I left this quite simple with a 10 nF and 1 nF cap, each in series with a 10 Ohm resistor.

It was really a surprise how much difference this simple device makes. There is a distinct clearing up of the sound, especially in the focus and articulation of the midrange. Vocals in particular sharpen in image size and the texture of the human voice becomes easily discernible. High frequency hash and the mess that happens when the recording mix becomes too heavy are cleaned up substantially by this.

Try it ! Its cheap, effective and really works.

Kingrex T-20U

2009-09-19T21:23:00.000-07:00

I have had the Kingrex T-20U for a few months now and so a post about this is long overdue.

The Kingrex has been around for sometime and has garnered a reputation for being one of the best sounding of the many low powered Tripath chip powered amps out there.

The designers of Kingrex must have paid careful attention to the many tricks that the DIY community were incorporating in Tripath amps as many of these tweaks and part changes can be found in the Kingrex such as :-

1. Film coupling caps
2. Premium air core inductors
3. Uprated low ESR local power supply caps
4. Heatsinked Tripath chip
5. Socketed op-amp for ease of opamp rolling (for the DAC only)

The icing on top of the cake is the Burr Brown PCM-2702E DAC with USB interface. Looks like this amp is clearly targetted at the PC audio crowd and you can say is perfect for powering small speakers on a computer desktop.

The T-20U is based on the Tripath TA-2020 chip which is capable of about 10-20 watts per channel into 4 Ohms (power varies depending on measured distortion level).

Rather than try to make this a detailed analysis of the circuit design and features of the T-20U, you would be better served to refer to the 6moons review on the T-20U at www.6moons.com/audioreviews/kingrex2/u.html

I didn't plump out for the matching linear power supply (hi-fi has a mysterious way of emptying the wallet ... so it has to wait for the time being), so any observation on the sound is based on the supplied switching power supply provided.

The Kingrex sounds like most other Tripath based amps. Quite similar in balance to my Trends TA-10.1, the Kingrex has a weighty and slightly full bass. I prefer Tripath bass compared to Icepower bass which is extremely tight and extended, to the point that I find the bass too prominent, attention grabbing and somewhat unnatural.

The midrange and high frequencies are fairly neutral and the slight lack of depth in the midrange and air in the high frequencies differentiate the Kingrex from its much more expensive competitors.

I don't do PC audio, so I did not have a chance to evaluate its USB input and DAC.

Keep the load easy (stick to a speaker between 4-8 Ohms and sensitivity of at least 89 db/w/m or higher) and the Kingrex represents a good value amp with clean and musical output that belies its price tag.

Comparison with my modded Trends TA-10.1 were most interesting. My Trends amp is moderately modified, with the following changes made :-

1. Coupling caps changed from Bennic metalised polypropylene to Auricap
2. Stock volume control changed to Panasonic miniature pot
3. Inductors shielded with copper
4. PCB tracks cut for direct wiring from RCA input to pot and back to coupling caps

The Trends was clearly better in every aspect and was also much cheaper to start off with. Sound was clearer and more coherent with low level resolution superior to the Kingrex.

I don't think this means that the Kingrex is a bad buy. However, it indicates that a stock standard T-amp (check out the many cheap T-amps on ebay nowadays) is capable of performing just as well, or even better than the Kingrex with some judicious modding.

The Kingrex is therefore suitable for the audiophile who does not have the desire or ability to mod the unit, or one who attaches a premium to the professional finished look of the Kingrex.

Diva Audio M7 Preamp - Latest update

2009-09-17T16:34:00.000-07:00

For all you Diva Audio M7 users out there, T.S. Lim has just revised his flagship M7 preamp.

The latest revision combines two stages of modifications.

The first stage involves new voltage supply filtering on both the B+ and the heater, combined with star ground wiring arrangement.

The second stage is a rewiring of the tube arrangement to allow easier tube rolling, and the installation of a new internal bracket that allows higher quality smoothing capacitors to be installed.

More on the tube rolling - previously the tube stages in the M7 are arranged as follows, the bottom tube uses one triode (the 12ax7 is a dual triode) as first stage, and the other triode as the second stage of the left channel. The top tube is identical and is used for the right channel. This then passes through the third stage in the middle tube (one triode for each channel). This means that you can only roll two different type of tubes at the most since the first and second stage use the same tube.

The M7 is now wired with each stage using one triode in the tube, i.e. the bottom tube is the first stage, the middle tube is the second stage and the top tube is the third stage. Now you can roll tubes to your heart's content.

Anyway, enough talk about the technicals. How does it sound ? I only managed to put in an hour of listening before sleeping but here are my initial thoughts on the latest incarnation of the M7 :-

1. Resolution - There is a noticeable increase in low level resolution and background "blackness". For example, on guitar notes, you can hear more of the body resonance of the guitar instead of just the plucked strings. Even in loud and complex passages, the increased level of detail is obvious.

2. Bass - Bass is substantial with more depth and extension.

3. Soundstaging - More 3D like with an noticeable increased in soundstage depth. Image sizes also are slightly larger.

4. Dynamics - The dynamic contrast between the loudest and softest passages is increased. Interestingly even at very high volumes, the dynamics are realistic and never fatiguing.

Note that my M7 uses a vintage military choke and NOS silver plated internal wiring. The volume pot is the standard Alps blue model though.

Oh yes, most importantly, T.S. Lim is offering this upgrade to existing M7 users for S$ 700. If you have already done the voltage filter and star ground, then the cost is S$300.

If you take this as an unreserved recommendation to upgrade your M7, you are not wrong. I highly recommend this upgrade. In current times when sought after NOS 12AX7 has reached silly money levels, this is money well spent.

Acrolink 2070II

2009-08-13T03:49:00.000-07:00

The Acrolink 2070II is the junior member of the 7N interconnect range of Acrolink of Japan.

I had earlier written about the 2400II which is the top of the range of the 6N interconnect range. An opportunity arose to acquire the 2070II at a decent price and I took it without hesitation. I have actually heard the 2070II before briefly at Audio Basic in Adelphi but did not want to consider it due to its considerable expense.

Physically, the 2070II and 2400II are quite similar in that they have a transparent outer insulation layer which shows off a metal braid shield underneath. Both utilize extremely bad and mean (I mean that in a complimentary way) looking RCA plugs that looks like they can be worn as hi-fi bling bling. Sporting carbon fiber bodies and rhodium plated pins, they certainly look the price and exude class.

The 2070II is physically larger and substantially heavier than the 2400II and its RCA plugs are quite large (and actually too close for comfort on tightly spaced RCA sockets). Owners of light weight T-amps beware, your cable will probably end up pulling down the amp if you are not careful. To its credit, the cable itself is relatively flexible. On an utterly trivial and sonically unimportant note, the 2070II comes is a beautiful wood presentation box that was stunning enough to lead my partner to hint that the box was perfect to store her jewelry in.

If you refer to my earlier posts, Acrolink cables have a house sound. Generally detailed, they have extended high frequencies and an overall airy feel to them. The 2070II does not disappoint in this respect. The 2070II differs from the 2400II in the following areas,

1. Bass – Most of the Acrolink cables I have heard are bass light or appear to be bass light due to their emphasis on the high frequency end. The 2070II does not suffer from this at all and has firm and tight bass with appreciable heft compared to the 2400II.

2. Midrange – The 2070II has less forward midrange projection compared to the 2400II. It sounds more mellow in comparison. Also, the midrange has a highly textured feel to it with fine nuances and changes in timbre clearly audible. The 2400II is like sitting a few rows closer with the midrange more 2-D like.

3. Treble – No surprises here. The 2070II continues in the Acrolink tradition of delivering the most beautiful shimmering highs with excellent communication of acoustic space of instruments and the venue. The extra expense here gets you even more refined treble with composure even in the most complex of mixes.

One interesting characteristic of the 2070II is the absolute blackness and quietness of the cable, as well as the sheer amount of micro-detail available. The 2070II in my humble opinion is a significant upgrade over the 2400II although it is quite obviously intended only for fairly high end set-ups given its cost. I like this cable very much. One reservation I have in general is that there is a nagging feel that what is being conveyed is not the truth, but rather than the manufacturer’s artistic impression on what music should sound like. Seriously though, if its artistic viewpoint is this much fun and musically satisfying, why not ?

B&W 804S Floorstanding Speakers

2009-07-17T04:09:00.000-07:00

I recently had the opportunity to build a system around the B&W 804S for a non-audiophile family setting up their first serious system.

They were brought around to audition a number of speakers, before they settled for the B&W.

For those unfamiliar with the B&W 804S, it is the smallest (its actually quite big physically) floorstanding speaker in B&W's 800 series line-up. At approximately double the price of the stand mount 805, the 804 has 4 drivers in a boat shaped cabinet with front firing port. Its a 3 way design with a Nautilus tweeter mounted on top of the cabinet.

On the rear, bi-wiring terminals are provided and jumper cables (not stupid brass links) with one end intelligently terminated with spades and the other with banana plugs, thereby ensuring compatability with cables terminated with either spade or banana plugs. Why can't all manufacturers do this ?

The B&W was heard twice in two different dealers. Pairing equipment included an all Arcam setup, Classe amplification and CD players and an all Cyrus setup. The B&W sounded very different through each of the three systems set up for demonstration purposes, suggesting that it is quite sensitive to matching with partnering equipment. Tonal balance wise, it managed to sound bright and fast with one setup and rich and somewhat slow on another.

Eventually, the 804 was paired with a Bel Canto S-300i. The combination is quite nice with very good grip and control over the lower registers and a neutral midrange tonal balance. The high frequencies manages to be extended with a fair bit of sparkle coupled with slightly rich bass. So who says your speaker can't sound clear and clean, while being weighty too ?

The B&W is versatile enough to handle varied music types with aplomb. Classical works, female vocals, jazz, rock and pop doesn't faze the 804 one bit. What I like about the 804 is that the presentation is not overly analytical. It doesn't stress out the owner by limiting him to a diet of audiophile recordings. Neither is it so non transparent that good ancillaries are wasted on it. A speaker of all seasons, it has enough qualities to please the hard core audiophile while being easy going enough to suit the casual listener.

One issue though is the local pricing in Singapore. This speaker retails for more than USD 5,000 (at today's exchange rates of about SGD 1.46 to USD 1.00) which puts it in serious speaker territory. There is a lot of quality competition at that price range, some of which are to my ears preferable to me compared to the 804. But I do digress. The 804 still warrants serious consideration, so do check it out if its in your budget range.

Bel Canto S-300i integrated amplifier

2009-06-29T09:54:00.000-07:00

The Bel Canto S-300i is a handsome piece of hear. Sporting arguably the thickest aluminum fascia I've ever seen, the fit and finish is absolutely stunning. From the tactile feel of its microprocessor controlled control knob, to the WBT binding speaker binding posts, everything feels perfectly balanced.

For a "digital" amplifier, the Bel Canto is also suprisingly heavy, about 5 kg. Based on a 150 wpc (8 Ohm) Bang & Olufsen Icepower module, the Bel Canto will deliver up to 300 wpc into a 4 ohm load.

Well enough about the specifications, how does it sound ?

According to conventional hi-fi wisdom, "Digital" amplifiers sound dry, synthetic and lifeless. Some early "digital" amplifier designs may have done nothing to dispel that myth. However, the Bel Canto has a fairly easy going sound. Extremely tight and fast bass, a warm midrange with the right amount of weight, what more could one ask for ?

I think the weakness of the Bel Canto lies in its presentation of high frequencies. There is a certain opacity and dryness to the sound such that hi-hats and percussion instruments don't really have much sense of air or space. You can hear the initial transient of the note, but without much feel of the decay thereafter. This weakness is not immediately noticeable but is revealed upon extended listening and comparisons with the other amplifiers I had at hand.

The above criticism has to be taken in context. The Bel Canto for its power is not an expensive amplifier (OK, its not a budget amplifier either). It proved very reliable in use, never skipping a beat or giving any cause for concern. I have built two systems around this amplifier for friends, and the results have been very satisfying. However, its overall balance requires careful auditioning and matching with partnering equipment.

An Afternoon of Tuning

2009-06-13T09:47:00.000-07:00

Saturday afternoon was spent over at a friend's place listening to his newly built Fostex FE168 Sigma in backloaded horn cabinets and the Diva Classic 1L preamp.

My friend has the honour of owning the very first set of the 1L preamp fresh from T.S. Lim's hands.

The Diva was paired with a modded Cayin A-50T. The Cayin does not have a direct preamp in socket, so the volume knob was either turned to maximum or about 12 o'clock (at times we felt the gain was too high with the knob at maximum). The Cayin is basically a power amp with a passive preamp stage inside a single chassis.

The modifications done to the Cayin A-50T include a change of input coupling capacitors to Jensen aluminum paper-in-oil capacitors. The other coupling caps downstream were changed to Sonic Cap MkI and the feedback caps changed to Solen. The grid stopper resistor has also been changed to Japanese Kiwame resistors.

The 1L has a beautiful yellow faceplate and uses an outboard solid state rectified power supply. The preamp circuit should be very simple (we didn't open it up) since there is only a single 6SN7 tube.

The Fostex was still running in, and we felt that although the tonal balance is quite nice, there was no bass, and very limited high frequency extension. Midrange definition also lacked some texture. Probably more extended run in would be needed before final conclusions could be made.

The full range driver strengths in terms of dynamics and coherence were all there, just that the lack of frequency extremes (this Fostex driver has no whizzer cone BTW and has an intriguing flower like pattern on its cone) and slight shoutiness made the sound a bit uneven.

First up, we rolled some of the tubes. The first to go were the small tubes in the Cayin. The 12AX7 and 12AU7 used there were JJ 12AX7/ECC803 and stock Cayin 12AU7 (almost certainly Shuguang). The 12AX7 tubes were replaced with RCA 5751 double mica blackplates and the 12AU7 replaced with RCA cleartops.

Flick the switch and hummmmmmmmm. Oops. Turned out the 5751 tubes were being a bit naughty. So, the JJs went back in. Wow, what a world of difference just with the change of 12AU7 tubes. Midrange was much more defined and the overall feel was more lifelike, focused and textured.

Other adjustments done included replacing the EL34 tubes of the Cayin with EH6CA7 tubes, and the stock EH 6SN7 in the Classic 1L which was replaced with a RCA GTB blackplate. Speakers were moved out a bit and toed in almost directly to the listener.

Ah... so much better now, although we both agreed that the very creamy and rich sound of the RCA 6SN7 GTB may be a bit too slow and warm for some.

My friend suggested we try the setup with another pair of speakers, Totem Sttaffs. Turned out to be the best sound of the day, but only with judicious repositioning of the speakers in the room.

The speakers were brought out far into the room and with slight toe in aiming to a point behind the listener position.

The bass was still slightly uncontrolled and a pair of socks had to be sacrificed to block the rear-firing ports of the cabinet.

Actually we had both written off the Totem Sttaffs before this point as my friend had quite a lot of problems with the Totem that sounded very dark with soundstaging and imaging problems. But he is now keen of keeping the Totem and fine tuning it to get the best sound possible.

It was a very fun two hours and we both learnt quite a fair bit. The tube rolling was quite a shock for both of us. Although I have always been a proponent of NOS preamp tubes, this is the first time I have heard such a day and night difference with just a single tube roll.

It will be interesting to see how the Fostex turns out after another 50 to 100 hours of run in.

Acrolink 6N Interconnects - Quick comparisons

2009-04-15T04:33:00.000-07:00

Acrolink 6N-A2400II

How much did I pay for this interconnect ? I am somewhat embarrassed to say. On the lookout for an upgrade from the Acrolink A-2110, looking at one of its higher end brethren seemed like a logical choice.

Speaking to the ever helpful Steven Cheah of Audio Basic in Adelphi, he suggested looking at the Acrolink 6N A-2400II. Residing at the top end of Acrolink’s 6N range, it is more than double the cost of the Acrolink A-2110.

Was anything wrong with my A-2110 ? Not really. It was enough to impress me in listening tests to warrant a purchase. And having listened to the whole gamut of cable out there from DIY Belden and Klotz to Audioquest, Mogami, XLO, Crystal, Siltech, that counted for something.

The A-2110 is a rather plain looking cable with a nude colour outer sheath terminated with very nice Acrolink RCA plugs. During listening tests when I first bought it, it quickly distinguished itself compared to the A-2050 II and A-2200 II which are the entry level models in Acrolink’s line-up. You can refer to http://www.acrolink.jp/english/products/6n_a2110_2.html for more information.

The A-2400II in comparison is a very impressive looking cable with a transparent gold insulating jacket, with the braided shield underneath quite visible. The RCA plugs in particular are a work of art. They are heavy, well made, and are rhodium plated. Part of the barrel is made out of carbon fiber. Full specifications are available at http://www.acrolink.jp/english/products/6n_a2400_2.html

The A-2110 has the characteristic Acrolink house sound – light, delicate with emphasis on a neutral midrange and shimmering highs, with very natural air around instruments and decay from transients. If the A-2110 had one drawback, it was the relative lack of bass compared to its sparkling highs.

Anyway, it was decided at Audio Basic that we would not test cables beyond the A-2400II simply because I was not willing to spend that much money on wire. A selection of tracks from Eva Cassidy’s Live at the Blues Alley were selected for comparison purposes.

By the end of the comparison, it was evident that the extra money had to be spent on the A-2400II. In fact, the miser in me had hoped that the A-2110 would prove more than sufficient. The A-2400II strikes you immediately as being a very quiet cable with absolute control over both ends of the frequency spectrum. Initially, it appears to be less dynamic than the A-2110. Further inspection reveals that the dynamics of the A-2110 are partly due to the slight messiness of its presentation. The crash of cymbals etc and resonance from percussive instruments can be slightly smeared in comparison. Also, when things really got busy, the A-2110 had a tendency for instruments to get lost in the mix.

As a matter of interest, my non-audiophile partner was asked to listen to 6 different interconnects. She commented on how similar the A-2110 and A-2400II were in terms of balance, although she had a preference for the A-2400II which in her words was simply better.

It was nice to see that diminishing returns did not set in for the A-2400II and the money spent was justified as compared to spending the extra dosh on upgrading other components in the system. IMHO, the expense of the A-2400II is fully justifiable in high end set-ups, where it is really able to strut its stuff.

As a matter of interest, I acquired a second hand A-2200II recently for another set-up. It is darker sounding than the A-2110 and has less treble refinement and extension. For that reason alone, I preferred the A-2110 which is more suitable in my setup.

A year or two after originally writing this post, I managed to get hold of the entry level 7N model, the A-2070 (please see my separate post on this). The bottom line for Acrolink is that you get what you pay for, with a corresponding increase in resolution, refinement and bass quality as you go up the range.

Hypex UCD400

2009-04-12T03:09:00.000-07:00

Over the past few years, I've dabbled with a number of "digital" amps (they actually aren't digital, but that's a whole separate discussion) and have had positive experiences with some of them to consider them seriously for a permanent place in my hi-fi systems.

I remember my first experience, the first generation Sonic Impact amp based on a Tripath chip with 5W output. The gasp that came from the small group that had gathered at my house was not really related to the sound, but more the shock that the tiny little amp could drive my Monitor Audio bookshelf speakers, powered by 8 AA batteries no less !

Fast forward, and I've tried a number of technologies including Tripath, proprietory (Flying Mole), B&O Icepower and now Hypex.

The Hypex was purchased second hand through a local hi-fi forum and was assembled by local modder and DIY supplier, James from Effective Audio Mod.

Here are some photos including some a shot under the hood. As you can see, it is a dual mono design with separate transformers and power supply boards for each channel. There is a motorised Alps potentiometer in front with a toggle switch, so you can use it as an integrated amp or power amp.

Sound wise, the Hypex seems to stray from the path of the sonic balance of most "digital" amps in that it avoids having the subterranean bass that seems quite common for these powerhouses. In fact, the sound of Hypex reminds me very much of the sonic balance of Tripath based amps.

The bass is quite well rounded with a certain amount of fullness (reminds me a bit of my tube amps ... of course my tube amps have much less control in the bass region). Its midrange is quite neutral with this balance maintained up to the high frequencies.

Amongst all the "digital" amps I've owned or heard, this one has the most pleasing highs. It doesn't sound etched, or dry. There is a nice sparkle and the communication of acoustic space is excellent. When listening to Patricia Barber's excellent drummer, the way the high hats shimmer is absolutely sublime. In case you think I really like this amp .... I do !

The above is with the built in passive potentiometer (Alps blue velvet). Paired with a Diva M7 tube preamp, the midrange becomes slightly fuller with the high frequency maintaining their shimmer but losing a bit of separation in favour of a slightly more organic presentation.

I also found that the Hypex matched very well with my Thiel CS 1.6. It had just the right balance to warm up the bass while maintaining the Thiel's neutrality and speed in the midrange and treble. What if you can't afford the Hypex ? Think seriously about a Tripath amp if you can get away with its power limitations. I have a Kingrex T-10U that I'll write about soon.

Quick and dirty comparison of 12AX7 and compatible tubes

2009-03-28T23:14:00.000-07:00

Here is a quick comparison of 12AX7 and 5751 tubes in my Diva Audio M7 tube pre-amp.

For those unfamiliar with the Diva Audio M7, it is a fairly popular tube pre-amp designed and built in Singapore by Mr. T.S. Lim. It is based on the Marantz 7 circuit and uses 3 12AX7 tubes.

Here are the observations of rolling the first tube position. Electroharmonix 12AX7 gold is used in the second tube position while the RCA 5751 blackplate (double mica) is used in the third tube position,

1. GE JAN 12AX7WA (1986 date code)

The tonal balance is dense with decent midrange and treble detail. However, dynamics seem a bit flat.

2. Golden Dragon 12AX7

The tonal balance is lightweight. A bit of a paradox, but the tube avoids brightness despite quite a lot of treble extension. Midrange and treble seemed smoothed out but the highs seem to go a lot further. I say it it a paradox to me, because this kind of extended response usually results in a fairly bright presentation. The lightweight sound probably comes from the lack of bass. This tube was a lot better than what I expected.

3. Sylvania 5751 gold pin (tripe mica)

My favourite tube of the lot. A lot of detail with both extended bass and treble. Very good air with good control of sibilance. Tonal balance is close to neutral.

4. RCA 5751 blackplate (double mica)

Dark tonal balance. Very smooth and creamy but compared to the other tubes, some midrange and treble detail is lost. I suppose its quite ideal in bright systems, but match with care. That being said, I've had very good results for this tube in other equipment.

Anthony Gallo speakers

2009-02-15T00:31:00.000-08:00

I had an opportunity to audition Anthony Gallo speakers at the local dealer recently, having been tasked to help a friend set-up a home theater system. Having an unobtrusive and stylish design was important, so the cute little spheres from Anthony Gallo seemed to be worth checking out.

The local dealer is econ-av and they have a small showroom on the first floor of Adelphi Shopping Center. You can have a look at www.roundsound.com to see the full range of Anthony Gallo.

I auditioned the Nucleus Micro, Micro Ti and the A'Diva Ti. The setup used for the Nucleus Micro and the rest were different (the Nucleus Micro was ceiling mounted) so comparisons may be due to mounting.

All 3 setups were auditioned with both hometheater and music.

First up was the Nucleus Micro. Based on looks alone, I would have chosen this. The cute little spheres come in very funky colors including bronze, glossy red and yellow.

As all 5 channels use identical spheres, steering is excellent with the panning between channels being seamless. Imaging is also quite good. Surprisingly the speakers sound more than decent with music and seem to go fairly low for their size (I estimate about 100 Hz). The dealer switched off the subwoofer and they actually sounded quite OK.

We switched over to the Nucleus Micro Ti. I didn't like it and it sounded too forward, crispy (not in a good way) with a noticeable tilt at the top end.

Finally, we listened to the A'Diva Ti. Very nice. Much of the quality of the Nucleus Micro while showing a noticeable improvement in weight and extension (the A'Diva is physically larger).

One thing I noticed is that the center channel sounds very small in comparison. Having listened to multiple driver center speakers my whole life, the dialogue seems in comparison to be less "centered" to the screen and lacking in depth. Having said that, I seldom hear conventional home theater speaker sets with such even panning from left to right.

Finally comes the sticker shock. These cute speakers sell for $2,000 for the 5.1 set (Nucleus Micro in plain finishes). Extra for exotic finishes. The Nucleus Micro is $2,800 while the A'Diva is $3,800. The matching subwoofers included in this package seem a bit small and it may make sense to pair the satellites with another active sub.

Pity. They really are cute and perform competently. The large markup over the U.S. price will make them hard to swallow for the local audiophile / videophile. Worth checking out if aesthetics are very important to you and you don't mind the premium.

There is an interesting product which looks quite similar from Orb Audio (www.orbaudio.com) which are priced more competitively. They are only available direct over the internet so comparisons will be difficult.

Trends Audio TA10.1 – Switched mode vs. linear power supply

2008-07-09T03:50:00.000-07:00

Introduction

The cute little Trends TA10.1 is a cheerful and useful little amp. Based on a Tripath chipset, it delivers 5 watts per channel and is perfect for a small bedroom, kitchen or office setup.

Used within its power limitations, it will not be embarrassed by amps many times its price. The Trends in particular is very modification friendly and my set has an upgraded potentiometer from Panasonic and Auricap coupling capacitors.

The stock power supply provided by the local distributor here in Singapore, Audio Trio, is a Chinese made switching power supply rated at 12V, 3A. Its hardly generates any heat, is light and compact.

Other users have reported varying degrees of success at using alternative power supplies, particularly units with higher maximum current rating, or linear power supplies.

Here is a comparison with a JVC linear power supply (bought from Koba Electronics at Peoples Park, Chinatown) rated at 12V, 2A. Heavy as a brick, it runs fairly warm and for some diabolical reason has the shortest DC jack cable I’ve ever seen.

Stock supply

There is nothing particularly wrong with the stock supply and performance seems relatively well rounded, with an attractively high amount of detail level. Instruments in jazz tracks like the saxophone, drumset etc, are well separated and precisely located in the soundstage. High frequencies are particularly airy with a shimmering feel.

If there is one criticism, the overall balance is relatively lightweight and bright, as the high frequency sparkle is not matched with a solid bass. Interestingly though, the bass is very tight and well controlled, but lacking in extension.

JVC linear power supply

The anti-thesis of the stock supply, the JVC linear power supply imparts a much darker presentation. Instruments do not pop out like the stock supply and image size tends to be larger but somewhat imprecise. Where the JVC stands out is the much heftier bass which has more impact and tilts the balance towards the warm side. The overall detail level seems lower and the sense of air around instruments is hard to discern.

Conclusion

Both power supplies have their place. Much like day and night, it is really up to individual taste whether you like a cool shimmering balance, or a dark and rich presentation. I was somewhat surprised by the differences as the reports I have read from other audiophiles suggested that the linear power supply was the way to go. Not quite a clear choice to me.

Coming up next - low powered digital amps

2008-07-01T22:37:00.000-07:00

Watch this space for an upcoming shoot-out between three low powered digital amps, the Sonic Impact T-Amp (the first generation model that started it all), the Trends TA-10.1 and the Nuforce Icon.

A tale of 3 power cords

2008-07-01T08:02:00.000-07:00

Do power cords make any difference ? Certainly. Do they improve the sound ? Questionable.

First, let's not get into the old and tired debate about why power cords make any difference. Miles of ordinary cable from the substation to our house and socket, and changing the last 5-6 feet of cable makes a difference ? Well, try for yourself and let your ears decide.

While on a powercord binge, I purchased some loose lengths of the following cables,

1. Acrolink 6N-P4030.
2. Oyaide Tunami GPX
3. Oyaide PA-23

Alll 3 cables could take on lead roles in a system depending on the effect you want to achieve. A short summary of their characteristics is listed below to give you an idea of how they sound. All cables were of course nicely burned in before any serious evaluation was done. I used plugs which I viewed as being commensurate to the cable's price range. Top end Oyaide plugs were used for the Acrolink and Tunami. The PA-23 was used with Wattgate plugs.

1. Acrolink 6N-P4030
This is a fairly thick cable and the most expensive of the lot, at S$ 160 per meter. It is not particular difficult to cut or terminate. Due to its thickness, it cannot be terminated reliably into a UK 3 pin plugs except for the ultra expensive Furutech UK 3 pin plug.

This cable sounds very refined and delicate. It has very good balance with its high frequencies being particularly expressive and detailed. It has a very special quality in the way reverb and decay are produced. The air around instruments is really fantastic and natural. For the price, I think it is a bargain.

Sonics : 9.5/10
Value : 9/10

2. Oyaide Tunami GPX

Another thick cable, and moderately priced at $100 per meter. It somehow seems to me slightly more difficult to work with compared to the Acrolink with its thickness being particularly problematic. Forget about UK 3 pin plugs and get the biggest and baddest plug you can find.

This is not a subtle cable. Deep thundering bass is its striking signature. Significantly darker than the Acrolink or the Oyaide PA-23, the Tunami GPX draws a bit too much attention to the bass. Nothing is particularly wrong with the rest of the frequencies, although its high frequencies definitely do not have that same magic touch as the Acrolink. Definitely what the doctor ordered for bass anemic systems, but others will need to match with care.

Sonics : 7/10
Value : 7/10

3. Oyaide PA-23
The skinny one of the lot, the PA 23 is flexible, easy to terminate and will fit into any UK 3 pin plug without complaint. At S$ 50 per meter, its cheap to boot too.

It has a lot more in common with the Acrolink than the Tunami GPX. It has a special delicate touch in the high frequencies with similar sense of air, and decay. What seperates this from the Acrolink is a relatively bass light response and the the lack of ultimate high frequency refinement which the Acrolink pulls off so convincingly. With the PA-23, you can sense the degree of extension in the highs (which is a touch hi-fi like). For the Acrolink, it just seems so natural, you forget about the cable.

For want of a better description, I think of this as a poor man's Acrolink.

Sonics : 8/10
Value : 10/10

Component matching is just like cooking. A bit of this and a bit of that, to balance all the flavours in the food. Throwing too many of any of the above cables into a system could be too much of a good thing. I use the Acrolink for my source, with the Tunami GPX for my amp. The PA-23is used for the source in my secondary systems.

US vs. UK mains plugs

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Singapore mains sockets use the 3 pin UK mains plug type. However, many local audiophiles choose to change their sockets to US mains sockets. What are the pros and cons between both ?

US sockets and plugs

Pros

1. No fuse (sonics wise)
2. No switch
3. US plugs accomodate thick and stiff power cables better
4. Large variety of aftermarket accessories

Cons

1. No fuse (safety wise)
2. Plugs use thin / folded blades
3. Against local electricity regulations

UK sockets and plugs

Pros

1. Fused (safety wise)
2. Plug terminals are sturdy solid brass type
3. Adheres to local electricity regulations

Cons

1. Fuse and switch degrade contact and sound
2. UK plugs do not accomodate thick wire well (except for the super expensive Furutech plug)
3. Hardly any variety of aftermarket plugs, sockets and cables

Interested to find out the difference between both options, I terminated two identical cables, except one with a US plugs and the other with a UK plug. The US plug was a budget Wattgate while the UK plugs was a hospital grade MK (the one with the red housing). The cable was the excellent and value for money Oyaide PA-23.

Both cables sounded different, but neither were obviously better. You could nitpick on the differences, but I don't think either could be reliably identified in a blind test.

I don't think you really should lose any sleep over deciding which to use.

Acoustic Reality ear 1001-Ref monoblocs

2008-07-01T08:00:00.000-07:00

I recently had the opportunity to experience the Acoustic Reality ear 1001-Ref monobloc which I had in my setup for about a month. Note this write up is for the 2007 model and not the current model which I understand has some circuit revisions.

Capable of delivering 500 watts per channel into 8 Ohms and 1000 watts per channel, it has more power than you could ever need.

Finished in shiny mirror cases with a shoebox footprint, it will look the part in a sleek and sexy setup. Apart from the annoying ability to show up dusts and fingerprints, you can use it comb your hair.

The ear 1001 Ref monobloc is based on the B&O ICEpower ASP1000 module, which is also used in the Bel Canto Ref 1000 monobloc.

They were given a work out powering a variety of speakers, both easy and hard to drive loads.

Many have complained that ICEpower sounds cold, dry and lacking in emotion. On the other hand, the number of hifi companies, including very respected names, suggests that the technology must have some merits.

Soundwise, the first thing that strikes you is the extremely tight grip on the bass. In the midrange to high frequencies, the extension and detail is incredible. Detail freaks will love these amplifiers.

Balance wise, it did not strike me as being cold or clinical (and these are comments coming from a tube lover). in fact the midrange seemed slightly laidback and full. However, there is a slight lack of fluidity and not much sense of air, so you will need to match with care.

Downsides ? The units appear to be very sensitive to grounding arrangement. Plugged into different wall sockets, the resultant hum was loud enough to take out a speaker drive unit which had me dive for the power switch. Plugging all equipment into the same power strip solved this, but this wasn't a problem I had with any of my other equipment before. Even with careful grounding arrangement, there was a very low volume hum audible about a foot from the driver units.

The gain seems to be fairly high too, and my excellent sounding Promitheus TVC preamp was way too loud even at the lowest setting. It seemed to like my homemade passive preamp (based on an Alps Black Beauty pot), but liked my Diva M7 preamp even better (which has a selectable gain switch anyway). The M7 combination mitigated many of the shortcomings I described above. So maybe, a tube pre could be a good way to go.

How would I rate this ?

Looks and build : 8.5/10 (nice shiny finish, WBT bindings posts)
Sound : 9/10
Value : 10/10

You can find out more about this amp at www.arhifi.com
BTW, there is no local dealer, so you have to direct order from the manufacturer.

Introduction

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Welcome to my hi-fi blog.

Details of my hi-fi adventures (not always good) and newsworthy information on the local hi-fi scene will be posted from time to time.

Do enjoy yourself and remember, hifi is a hobby at the end of the day. Have fun, enjoy yourself and don't take things too seriously.