The Sony TA-A1ES (I will refer to this as the "A1ES") integrated amplifier arrived at my doorstep together with the HAP-Z1ES. There has not been much news or reviews of the A1ES which in my opinion, is a great pity - this is really something quite special.
A trickle of products in recent years suggests that Sony is quite serious about re-entering the high end audio arena, and judging from the quality of products I've evaluated (the A1ES included), they are certainly on-track.
Description
The A1ES is a compact unit, measuring 430 mm x 130 mm x 420 mm (W x H x D). The dimensions are quite deceptive, and lifting it out of the box required a fair amount of effort - I found out later that the unit weighs 17 kg.
This is a wide bandwith design (10 Hz to 100 KHz), with 60 watts per channel on tap. Some noteworthy design features include a discrete component preamp circuit, a smart bias system, and a separate headamp circuit also utilising discrete components. To maintain sonic purity, the A1ES utilises a single pair of transistors per channel. I was reminded of a very interesting conversation I had with another leading manufacturer that believed strongly in the merits of this approach versus multiple transistors in parallel.
The smart bias system varies bias according to volume position in order to reduce excessive heat while maintaining transistor linearity. Conventional class A operation amplifiers are highly inefficient, with high power consumption and heat when idle. Varying the bias across the output devices is not a new idea, with various approaches in the past, e.g. varying bias with the signal level and/or output current, or having multiple bias steps. These approaches have the advantage of reducing bias at low signal / load levels, which reduces heat levels considerably. I found the Sony to run quite hot - you wonder how much hotter it would run without any form of bias management !
A knob next to the headphone jack selects the impedance range of the headphone used. The low impedance headphone setting selects low gain, and correspondingly, medium and high gain for the mid and high impedance settings. This helps address the problem of high levels of noise, and excessively "hot" volume control for low impedance headphones / IEMs, and insufficiently volume into high impedance headphones. The headamp circuit puts out a very healthy 500 mw per channel, into 8 ohm or 150 ohm loads, and 250 mw into 300 ohm loads. This should allow it to drive most headphones on the market, except some very unfriendly loads like some of the magnetic planar headphone models out there.
A speaker impedance setting on the rear panel toggles between two positions, 4 ohms and 8 ohms. The manual does not explain why this is required, but a wild guess is that it alters the smart bias curve based on a rudimentary estimation of current draw.
Feature wise, five line level inputs are provided, one of which are balanced. An auto standby switch allows the amplifier to switch off when no signal is sensed for a while. The unit comes with a remote control. The over-sized speaker binding posts had the most smooth operation I've come across regardless of price.
Sound
Paired with my Monitor Audio GX100 speakers, the A1ES struck me as having a supremely confident and effortless sound. I was pleasantly surprised at the amount of grip and control the Sony had over the speakers. This turned out to be the forte of the Sony - it had a punchy and fast bottom end that is really quite uncommon for a product in it's price range.
The midrange had a slightly laidback quality, with a subtle sweetness. Female vocals were reproduced with a silky tone that was natural and free from grain. I found the A1ES to be very easy on the ear over long listening sessions - perfect for unwinding but maybe not if you like a more forward and incisive tone.
High frequencies were clean and detailed, with a good "sparkle" and sense of air. I found the balance to be just right, with good behaviour and "bite" when required. One point worth noting is that both high and low frequencies would best be described as slightly dry - make sure this is paired with sympathetic equipment.
I also found the A1ES to be highly resolving, with very good detail retrieval and precise imaging and staging. Image sizes were on the smaller side though, and flatter in perspective compared to my reference equipment (my Gryphon Diablo - let's not forget that the Diablo's price tag is many times a multiple of the Sony)
I tried hooking up a pair Thiel CS 2.7 speakers next (with the speaker switch set to 4 ohms) - results were quite good, but somehow the Thiels did not sound as effortless and spacious as the Monitor Audios. Possibly, the Sony should be paired with easier loads.
I also took the headamp stage for a spin - very nice indeed. I am sure it would be good enough to replace a mid-range headphone amp. Much of my observations above apply to the headamp stage when paired with my Beyer DT880 headphones (250 ohm version).
Conclusion
The drawbacks noted above are very minor in the context of the price level of the Sony. In fact, I found the A1ES to be way off the charts in the value-for-money stakes. Audiophiles exasperated at the ever rising cost of equipment really should look at the A1ES.
It keeps your system as simple as possible and delivers a glimpse into high-end performance, at a cheerful price that puts this within the reach of most audiophiles. For the money, it really doesn't get any better than this !
Highly Recommended and Best Buy
A big thanks goes to Sony Singapore for supplying the review set, and it's media partner Waggener Edstrom for making all necessary arrangements.
Recommended Consumer Price - S$ 2,499.
