May 2011

World Premiere!
Shengya A-206MK Integrated Stereo Amplifier
An extraordinary bargain!
Review By Tom Lyle

  I've usually taken the liberty of assuming that the readers of Enjoy the Music.com aren't newcomers to the audiophile community. By this I do not mean that I am only writing for those who only consider auditioning and reading reviews of super-expensive state-of-the-art components. But what I mean is that I usually assume that most of our readers have a bit more than a basic understanding of not only certain electronic principles, and of the language that audiophiles use in communicating how those electronic and physical principals relate to the (hopefully high) quality of the music that flows forth from these components under review. But let's face it, this can be a rather expensive pursuit, so I get quite a kick out discovering components that not only sound great, but give one quite a bit of what one not only expects, but demands, from a component that is sold as “high-end” audio at less than exorbitant prices. And I get even a greater thrill when I come across a product that cost much less than one would expect for a fine level of sound and build quality. The Chinese designed and built Shengya A-206MK solid-state integrated amplifier is one of these components.

Of course this is not likely to be the first “high-value” component that you've ever read about, nor is it not the first one I've ever reviewed. But as the saying goes, there is no such thing as a free lunch, so as a consequence, when one pays less for a solid-state amplifier one usually expects lower power, a more lightweight chassis, and at least some quirks within is character that would require matching with other low cost components. Yet the Shengya A-206MK is a 200 Watt per channel, 68 pound, nearly 2 foot deep almost nine inch high, class A/B integrated amplifier that can double as a straight-through power amplifier and can be had for under two grand from their North American distributor Grant Fidelity. But most importantly, this amplifier sounds as good as its promotional literature proclaims.

Commitment
One can get a rather good idea of this Chinese company's serious commitment to the field of high-end audio by reading editor Steven R. Rochlin's Shengya factory tour that he was lucky enough to attend in 2009. The tour should dispel any lingering negative stereotypes regarding any underage factory workers or poor working conditions, as their skilled staff is seen pursuing their craft in a pristine environment. Shengya has been in business for about 18 years now, run by a husband and wife team, he on the design end and she on the business end. When they first started out their main focus was on tube amplification, and an emphasis on Class A circuits. Shengya now offers a wide range of products from source components to speakers, and of course amplification.

The A-206MK integrated amp is a true Class A/B fully balanced amp, running entirely in Class A for its first full 20 Watts of operation, and then switches to Class B above that. Class A/B amps are not uncommon, but to remain in Class A for as many as 20 Watts is. The remote controlled A-206MK is a revision of the A-206 (sans MK) that allows the unit to bypass the preamp section completely and operate as a dual mono power amp simply by connecting a preamplifier's interconnect to the input marked “Main Input”, and choosing that input via the front panel or on its supplied remote. Shengya claims that their A-206MK uses a proprietary, high-speed DC chip which enables the amp to deliver an “ultra-wide frequency response, an extremely low measured level of distortion, and a refined yet grand soundstage” (note: their use of English language in their literature is more than a bit stilted, so I am going to assume by “grand” soundstage, Shengya is saying that they feel that the soundstage is excellent). The output stage of the amplifier has a 500 Watt shielded transformer, MKP (metalized polypropylene) capacitors, and is designed with a fully discrete output circuit with 16 high-power transistors.

The A-206MK has five gold-plated unbalanced RCA inputs, one of which is the direct input to the amplifier, bypassing the preamp section. There is also one balanced XLR input. The amp also has two pairs of heavy-duty speaker binding posts per channel, making it possible to bi-wire one's speakers using an additional pair of standard speaker cables. Large volume and source selectors as well as its small power and mute switches occupy the front panel, and on the lower portion of the front is rather large readout that indicates the volume, input, and channel balance. An often neglected feature – a channel balance – is controlled from the remote, and this remote is not a flimsy plastic OEM job that is provided all too often with equipment that deserves better, but rather an easy to use slim aluminum module manufactured by Shengya.

The A-206MK is also quite a looker, if one can appreciate its fortress-like appearance that sports thick black brushed aluminum casework along with silver pillars flanking the sides of its front panel. The top plate of the cabinet of the A-206MK, with its sort of industrial-chic look, has a row of six approximately 2” apertures with silver-colored grilles along either side of the top cover. There is also a large inscribed name plate on the top section closer to the front of the cabinet proudly displaying the Shengya “S” logo and the name of the integrated amp. The amp became quite warm (I'd venture to say the temperature of the top of the cabinet surpassed “warm” and became rather “hot” during normal use, but this never became problematic even with only about 6” of clearance between the top of the amp and the next shelf of the equipment rack). Oversized heat-sinks cover the entire side of the amp, which made lifting the amp onto the Arcici Suspense rack I use in my main listening room a challenge, but not impossible. Although because of these heat sinks and the uneven load the amp presented I had to violate just about every rule of correct lifting. Lifting this amp into position is really a two-person job, so do what I say, not what I did.

Started
I started my review using the Shengya A-206MK “only” as a power amp, but then connected all the front-end equipment to the A-206MK and used it as an integrated for quite a while longer. When I used it the A-206MK as a power amp I connected the output of a Balanced Audio Technology VK-3iX directly to the A-206MK using an unbalanced RCA cable to input 5, which bypasses the preamp section of the amp. The analog front-end of the system is a Basis Debut V turntable, with a Lyra Kleos phono cartridge mounted on a Tri-Planar VII U tonearm. The Tri-Planar's hardwired RCA interconnect fed a Pass Laboratories XP-15 phono preamp. I occasionally use a vintage NAD 4155 FM tuner for off-axis enjoyment of WFMU (free form), WQXR (classical),  WKCR (mostly jazz), WBGO (jazz), WSOU (hard rock) and some others given that there are a plethora of decent terrestrial FM stations in my listening area. Digital sources include a 3.20 GHz/8G RAM PC running Windows 7 with 4TB external hard disc storage using Foobar 2000 and MediaMonkey v3. The USB cable from the PC connects to Benchmark DAC1Pre. Also connected to the Benchmark's S/PDIF inputs are an Arcam DiVA CD192 CD and an Oppo BDP-83SE for physical CDs that I play every so often. The Oppo's stereo analog output feeds directly to the preamplifier for spinning SACDs and the few DVD-Audio discs in my collection. I also still had on hand for the first part of my audition period the quite enjoyable Internet radio/DAC made by Opera, the Consonance D-Linear 7/8 combination that I reviewed in February 2011 issue of Enjoy the Music.com.

Speakers are the Sound Lab DynaStat hybrid electrostatics sometimes aided by a Velodyne HGS-15b subwoofer. Interconnects are mostly MIT, and power cables are mostly from Virtual Dynamics. All the power cords running from the digital front-end (other than the computer) and the preamplifiers are connected to a PS Audio Power Plant P600 AC regenerator, and the turntable's AC cable is connected to its own P300 Power Plant set at a pure 60Hz (81 Hz for 45 rpm records) sine wave. The electrostatic panels' and subwoofer's AC are connected to a Chang Lightspeed power conditioner, and everything is then connected to two separate dedicated AC lines outfitted with Virtual Dynamics  wall receptacles. I plugged the Shengya's power cable directly into the wall. At first I used the stock power cord, but I heard a marked improvement in its sound when using a high-quality aftermarket power cord. The listening room is treated with Echobusters acoustic room treatment panels, the medium to largish room's floor is covered in industrial grade carpeting, and its plaster walls are painted a soothing sky-blue.

Broken-In
The break-in period wasn't one I would call excessively long, perhaps only after about fifty hours of use the A-206MK was more than 75% broken-in, after that I'm not sure it slowly worked its way towards fully broken-in, or I just became accustomed to its character. And the most noticeable characteristic was that this was a 200 wpc amp that belied its power specifications. The Sound Lab speakers in my main system are awfully difficult speakers to drive unless supplied enough current and power, and the A-206MK did not disappoint at all in these areas. Kudos must be given to the A-206MK as the sound qualities of the amp changed little regardless of whether I was listening to an LP of a minimally-mic'ed chamber group playing a Brahms quintet  or a digital file of a multi-tracked power-trio rock out at full throttle.

The A-206MK's bass response was deep, tight, extremely pitch stable, and free of bloat, and most noticeably true to the source that was feeding it. I spent nearly half the review period with no subwoofer augmenting the main speakers. Sound Labs publishes the specifications of their DynaStat's frequency response as being able to reach down to 27 Hz, and I have no reason to doubt this, although they don't give the accuracy of that rating. And so in real world listening I guess it depends on the listening room and the position of the speakers, but in my room I'd guess useable bass would go down to the mid-20s. At least. But this is with test tones, so when it came to “real” music, the only things that truly came through at this level were organ pedal tones and concert bass drum. The A-206MK let me feel as well as hear the bass coming through their two 10 inch woofers in the ported enclosure of the large-ish bass modules of these more than six foot tall speakers, of course mostly taken up by the electrostatic panels. But the bass cabinets that take up the lower portion of the speakers certainly made themselves heard -- given the proper material.

Two digital discs outperformed all others in this region during the listening session were the bass drums on the SACD of RiccardoChaillly leading the Concertebouw in Mahler's Third Symphony on Decca at the start of the first movement, and the organ pedal's on the 16-bit/44.1kHz file in the third movement of Vaughn Williams' Seventh Symphony (Sinfoniaantartica) on Naxos of KeesBakels leading the Bournemouth SO. It was nice that both these discs feature impressive feats of music making by both the performers and these respective composers. So, as I was more than hinting at before, it wasn't just the power and the glory of the bass response, but the quality oozing forth from the woofers -- not quite pressurizing the room – as there are only two 10” woofers – but the amount of the bass, and especially the quality of this bass was enough to portray all that was going on during the original event on which these recordings were based. Of course adding the subwoofer added the sub-sonic heft (and room vibration) that transformed the system's very low bass response into very, very low bass response. To the A-206MK and the system's credit, before I added the subwoofer to the system I hardly thought the sub was necessary. That was, until after I added it.

I'd feel a bit silly if at this point I simply moved up to a discussion of  the Shengya A-206MK integrated amplifier midrange prowess, and after that the treble response of the amp. Yes, it might give one a good sense of the capabilities of this unit, but it would hardly give the sense that that this amp is reproducing music that is more than just an assembly of a bunch of pieces of the audio spectrum. But still, its bass response was definitely one of its strong suits. This is not to say that the sound of the rest of the amp was lacking. It wasn't. It definitely punched way, way out of its weight class not only in the bass, but in the rest of what one would consider important in all areas of sound reproduction. When using the A-206MK as a complete integrated amplifier, which I assume is how the majority of users will employ it and how I used it for most of the review period, the characteristics that I discovered when using it as a straight power amplifier were almost exactly what I thought of its character when using it as just an amplifier. In short, the A-206MK leaned to the analytical side of neutral but without ever sounding etched or strident, and generally had very little character of its own imposed on the source material. I assume that most listeners would rather an amplifier err on the side of detail than loss of focus, and the A-206MK was a force to be reckoned with when considering the sheer heft that imparted unto the music.

I've used the second Stooges LP Fun House as pressed by Sundazed Records before in my reviews, and if I haven't I surprised, since I've been listening to this pressing on a very regular basis since its release. Hardly an “audiophile” recording no matter which categories one considers, other than the most important, which is how one can imagine one is eavesdropping on the original even that occurred in the studio's control room during the session. Unfortunately, very few survive that were there that day in 1970 at Elektra Sound in LA, but to be sure, the energy of the band bleeds through the speakers regardless of the quality of the audio equipment that is playing this record. But when all is right with the gear and one is in the mood for a slamming rendition of Iggy Pop bellowing she got a TV eye on me--oh--right on, right on, right on, Dave Alexander's Fender bass growling underneath Scott Ashton punishing the skins on his drum kit, all the while brother Ron is terrorizing his six-string Marshall-stacked Gibson – in unequaled drunk-rock perfection. But even when judging the sound of this LP through perfectly objective ears, one could hardly ask for a more honest portrayal of a minimally produced rock album. And a classic.

Compared to more pricey amplifiers, in addition to its slightly more detailed sound than ideal, its other faults were subtractive – not in its frequency response, but rather in soundstage depth, and what I like to call a “wrap around” sound, that is, hearing the ambient sounds that might either be live in a concert setting, or man-made in a recording studio. Seasoned listeners will know exactly what I'm talking about when I speak of “dynamic distance”, or the separation of sounds that might be occurring simultaneously at different volumes, and the ability of a piece of audio equipment to reproduce this difference, regardless of where in the reproduction chain the piece of equipment is located. And, again, this fault is only recognizable when compared to much more expensive pieces of equipment. So, regardless of whether I may seem to be harping on the negatives, there is really not a whole lot more to complain about the A-206MK's sound, and a whole lot more to praise, especially its faithful reproduction of the source material that was placed before it. So, for a better integrated amp one is going to have to spend quite a bit more, and even quite a bit more than that if one is considering a separate amp and preamp to get this level of sound quality. And even more for an amplifier that can deliver this much power so effortlessly.

Those who are familiar with my “reference” system, are well aware that usually in my main listening room are a separate preamplifier and power amplifier as opposed to an integrated amplifier. I have nothing against integrated amplifiers, especially these days where the choices are hardly as limited in regards to power. Integrated amps were once only for those who needed a low powered single-box solution in a small package. Those days are over. But one of the reasons I prefer a separate amplifier and preamplifier in my main system is because I like to combine a tube preamplifier with a high powered solid-state amplifier. That's just me. The electrostatic hybrids that reside in my main listening room demand lots of solid-state power, but the preamplifier section is more of a matter of taste than anything else. When pairing a tube preamplifier with a solid-state power amplifier I've discovered the best of both sonic worlds. In my system. So bear that in mind when I speak of a slightly more detailed sound than ideal when using the Shengya A-206MK, because it is possible that when using your speakers of choice, your mileage may vary.

Bargain
The Shengya A-206 MK integrated amplifier is an extraordinary bargain. With 200 Watts of power per channel, a rather transparent sound, solid construction, plus the option of using it as a stand-alone power amp makes it just about irresistible. The preamplifier section is a bit lacking in the features department – it is nice that it has a balance control, but I'd trade it for preamplifier output and/or tape-out in a second. Its sound leans more to the detailed side of things, so that might manifest itself as a bit of brightness in some systems. Yet this might be more of a matter of system matching than anything else. For those that need a basic integrated amp and need lots of power, and would like to save some money while they're at it, here is your integrated amplifier, ready to go.

Ratings
As usual, my conservative rating are based on a five note rating reserved for the best I've ever heard from any component in its category.

Specifications
Type: Solid-state integrated stereo amplifier
Frequency Response: 10 Hz to 20 kHz (±0.5dB)
Power Output: 200 Watts RMS per channel at 8 Ohms
Class A power output 20W per channel at 8 Ohms
Total Harmonic Distortion: 0.1% (1kHz 1W) 
Input Sensitivity: 300mV
Signal To Noise Ratio: 90dB
Input Impedance: 47k Ohms
Dimensions: 18 x 8.5 x 20.5 (WxHxD in inches)
Weight: 68 lbs.
Price: $1750

Company Information
Shengya Audio
Website: www.shengyaaudio.com

North America

Voice:(403) 984-3882
E-mail: grantfidelity@gmail.com
Website: www.grantfidelity.com