Weiss DAC204 Review

Introduction

Weiss is best known for their professional products which see use in studios worldwide. They have seen success too in their domestic products and I personally know a number of discerning audiophiles locally that use Weiss products. 

As an owner of an INT204 USB/DSD interface, I appreciate the level of quality and performance delivered. Not cheap by any means, but their products are priced reasonably, especially in the context of current high-end pricing.

Description

The Weiss DAC204 is a compact shoe-box-shaped device that combines the DAC board of the DAC205 with the functionality of the INT204 USB/DSD interface. The DAC205 offers only a Toslink and coaxial input, making the DAC204 the unit of choice if you require a USB input. Based on an oversampling sigma-delta D/A convertor, four paralleled D/A convertors are used per channel for superior signal-to-noise performance. High jitter suppression is claimed by virtue of several signal re-clocking schemes.

The USB input supports sampling frequencies of up to 384kHz and DSD64/128 (sampling frequencies of 352.8 and 384kHz are downsampled to half the original frequency). Two front panel toggle switches convert DSD signals to PCM at either 88.2kHz or 176.4kHz sampling rate and 16 or 24-bit word-length. The coaxial and Toslink inputs accept signals of up to 192kHz. 

The flexibility offered by the DAC204 is tremendous. Three digital outputs (coaxial, BNC and AES/EBU) allow digital signals to be routed to another DAC or digital recording device. For example, the DAC204 could be used with legacy DACs that neither have a USB input, nor DSD compatibility. 

Turning to the analog outputs, both single-ended and balanced outputs are available, with four selectable output voltages (0.23V to 7.5V for the balanced output, and 0.115V to 3.75V for the single-ended output). This allows the DAC204 to be adjusted based on the gain structure of your system. The higher voltage settings would be especially useful for passive preamp users. 

The power supply is off-board, with a medical-grade switched-mode power supplied. The DAC204 accepts a supply voltage between 6 to 9V DC, with a current requirement of 1050 ma at 6V or 700 ma at 9V. Weiss will also sell you the PSU101 universal power supply if you wish to upgrade the performance of the DAC204. Just be warned though, it's as expensive as the DAC itself!

In use

The Singapore distributor for Weiss kindly included a Plixir Elite 6V-6A power supply and Statement DC cable to try out with the DAC204. I used both the Plixir and the stock power supply during my evaluation. 

I hooked up an old CD player to the coaxial input to run-in the unit. None of the sampling frequency LEDs lit up although music flowed. Reading the manual again, I realised that the LEDs only light up when using the USB input. Apart from this initial scare, the DAC204 performed without any issues.  

Sound Quality

With the Plixir, the DAC204 impressed with a highly detailed and cohesive sonic performance. The first thing that strikes you is how music flowed without any particular frequency calling undue attention. 

Bass was tight and impactful and had good speed and tempo. Vocals had a mild laidback quality that provided some warmth to the human voice. High frequencies were reproduced with a clean and crisp edge. The Weiss managed to strike a perfect balance - with a detailed and grain-free midrange and good highs without sounding bright or strident.  

Readers to this point would be wondering what made the Weiss special compared to competition? In my view, the DAC204 was able to convey a superior sense of dimensionality and realism - with clear illumination of the acoustic space around each voice and instrument in the recording. I associate this particular quality with high-end DACs which is high praise indeed for the Weiss. 

The subtly warm tone and lack of harshness allowed for many hours of fatigue-free listening. Despite the professional audio heritage, the Weiss struck me as a musical device - I spent most of my time enjoying the music instead of trying to dissect the recording. 

Swapping out of the Plixir for the stock power supply greatly diminished the performance of the Weiss. Apart from losing impact and power in the low-frequency region, the drop in resolution and separation was obvious. 

Conclusion

Sonically compelling with the Plixir power supply, the Weiss offers great flexibility in a small format. The price with upgraded power supply is well justified if you require the functionality of the INT204 board - Recommended.

I would like to thank Sound Affairs Pte Ltd for arranging this review. 

Weiss DAC204 D/A Convertor

Price - S$ 3,996 (with stock power supply), $5,000.40 (with Plixir Elite BDC and Statement DC cable)

Sound Affairs Pte Ltd

110 Lorong 23 Geylang

#06-03 Victory Centre

Singapore 388410

http://mysoundaffairs.com

 

Weiss Medus DAC

Introduction

In Greek mythology, Medus was the son of Medea. Perfect naming from Weiss as the Medus DAC is the successor the Medea. As a health / financial advisory,  weak hearted and/or weak wallet audiophiles should not read any further. 

The Medus is Weiss Engineering's all-out assault to produce "the best Digital to Analog Converter money can buy."

Description and Features

The compact dimensions of the Medus do not hint at the weight of the unit. Moving it onto my hi-fi rack reminded more of a small integrated amplifier !

Fit and finish are superb – visual inspection and the touch test leave no doubt that you are dealing with Swiss precision engineering here. The tactile feel of the panel buttons (and even the remote control), chassis, screws etc. – everything is top-notch. In fact, the solid metal remote control alone is better made that most of the consumer audio equipment on the market.

The Medus is constructed out of an inner steel chassis, which is in turn encased within an aluminum frame. According to Weiss, the inner chassis forms an effective shield against electrostatic and electromagnetic radiation while the outer frame acts as a further shield and maintains optimal heat convection.

The front panel buttons control power and input selection. The central  display provides information on the selected input, bit resolution, sampling rate, attenuation, phase, and the selected upsampling filter. Information on the set level of the output stage is momentarily flashed when adjusted (see below for further details).

Set out on the rear panel are the IEC connector for the detachable power cord, analog outputs (single ended and balanced), and four grouped digital inputs. The digital inputs are grouped (e.g. digital input 3 is an AES and USB input), and only one input can be used. The AES sockets on inputs 1 and 2 can also be used for dual wire AES. All inputs support sampling rates of up to 192 kHz. The asynchronous USB input (actually an onboard Weiss INT204) also accepts DSD 64 and 128, albeit converting it to PCM.

Firewire and a ST glass input can be ordered also as an option.

A DSP chip up-samples 44.1 kHz and 48 kHz content to a minimum of 88.2 kHz using Weiss’s in-house up-sampling algorithms. The DAC chip then up-samples the input signal to about 1.5 MHz. Four D/A conversion channels are used for each of the stereo channels.

Weiss utilizes its discrete opamp design, the OP1-BP, for both I/V conversion and for the output stage. The technically inclined may wish to refer to the published datasheet on the OP1-BP’s design. Specifications are excellent, with very robust drive capability (even into low impedance loads). The output stage operates in Class A and is DC coupled without any use of servos. A total of eight OP1-BP modules are used in the Medus. The latest versions of the Medus use the newest version of these modules, the OP2-BP. I confirmed with Sound Affairs that the unit passed to me for review uses the OP2-BP.

The single toroidal transformer is used for the linear power supply, and is shielded using a mu-metal cover to minimize leakage of stray fields.

Volume control can be set in two different ways. The first way involves adjusting the maximum level of the analog output stage, which can be set in 1 db steps from -4 dBu to +27 dBu (17.35V) for the balanced output, and from -10 dBu to +21 dBu (8.67V) for the single ended output. The second way utilizes a digital volume control which operates from -60 dB to 0 dB in 0.5 dB steps. A small turn pot (which acts as an optical rotary decoder) is situated between the two balanced analog outputs and allows setting of the analog output level, but it is far more convenient to set it using the remote control.

Setting the level of the output stage permits fine tuning to suit the overall gain level of the whole signal chain (overly sensitive volume controls anyone ?) while using higher than normal levels could assist the passive and transformer based volume control crowd. If you are skipping a preamp altogether and setting volume on the Medus, you could adjust the analog output levels to minimize the use of the digital volume control since aggressive digital attenuation results in lowered resolution.

Operation

The USB input of the Medus did not get along with my Auralic Aries. Although the Aries detected the Medus, any attempt to play music was in vain, with the selected track remaining paused. Switching to AES solved everything, and thereafter the Medus played any PCM file I threw at it without incident. The issue almost certainly lies with the Auralic which alternates between being on non-speaking terms, or being in a stormy relationship with a number of my other DACs. In any event, the Medus got along just fine with a Macbook Pro running Pure Music 1.89 (both PCM and DSD) via USB.

Another point to note is that during sampling rate changes, the muting relay activates for quite a long time. When running via AES, I had to add a 5 second delay to the Auralic to avoid cutting off the first few seconds of the next track. I did not notice any such issues using USB.

The Medus was left switched on permanently during the time I had it for review. After a few hours, the Medus is quite warm to the touch. 

I did not fiddle much with the settings. Between the two filters, I had a preference for Filter A. I also found that the digital volume control gave the sound a "soft" quality - impacting leading edge definition and dynamics. 

Sound Quality

I spent a few days trying to get a handle on the sonic quality and character of the Medus. The conclusion is that the Medus is easily the most transparent and neutral DAC I have heard in my system to date. The character of the Medus (or lack thereof for that matter) is wholly dependent on the recording. Given Weiss’s extensive experience in the pro-audio and studio recording industry, I shouldn’t have been surprised in the least.

On the downside, there is no attempt to flatter poor recordings – you get everything, warts and all. However, unlike some other equipment I have heard, the Medus does not attempt to “spotlight” details. Instead, information is retrieved and presented in the three-dimensional perspective and tonality in the fashion which I believe was intended by the recording engineer.

The Medus has superb performance across the whole frequency range. Low frequencies are tight, controlled and have excellent articulation. Whether it is a kick drum or double bass, the Medus has class leading punch, definition and clarity. Midrange clarity is similarly natural. There is no smoothing over of sibilance, nor added emphasis to increase "presence". High frequencies are reproduced cleanly, with a crisp, clear and astonishingly grain-free tone.

The Medus easily sails through the typical audiophile tests. It has the finest resolving capability. It has astounding dynamics when called for. It renders as wide and deep a soundstage as required. The list goes on.

I was particularly impressed by the way the Medus reproduces the tone of the violin and piano. The violin is reproduced with an ideal balance between fullness and bite, while piano is rendered with authority, attack and body. In short, I enjoyed the most realistic presentation of these instruments in my system to date.

Needless to say, I was very sad when the Medus had to be returned at the end of the review period.

Conclusion

The Medus is the DAC of choice for high-end systems that require a neutral reference point. For the discerning listener that demands the finest quality of reproduction as intended by the recording engineer - the Weiss Medus ticks all the boxes.

The stumbling block for many would be the price - the Medus is priced beyond the reach of many audiophiles. I am keenly aware that the competition is priced similarly (and even higher in some cases !), and I do consider the Medus to be reasonably priced given its level of performance.

Truly outstanding performance - Highly Recommended. 
The review unit was kindly arranged by James Soh of Sound Affairs Pte Ltd, the SIngapore dealer for Weiss.


Weiss Medus DAC

List Price : S$ 32,000


Sound Affairs Pte Ltd

100 Beach Road, Shaw Tower
#02-34/35
Singapore 189702
http://mysoundaffairs.com