I first heard about the solid-state Soulution 710 about a year ago. This hefty (176 lbs., uncrated), 240Wpc (into 4 ohms) Swiss-made stereo amp had already won a number of prestigious awards in Europe and Japan from magazines that are persnickety. What was more surprising were the superlatives that accompanied the awards. Several of these magazines outright declared it the "best amp EVER," which was definitely out of editorial character.
Anyway, I did a little research, took a look at Soulution's Web site (www.soulution-audio.com/english/e_710.html), and was surprised to see Soulution talking about combining the virtues of tubes and transistors. (A hardcore, ultra-high-tech, Mega-Hertz-bandwidth transistor outfit conceding that tubes had virtues that solid-state didn't was, to say the least, unusual.) Intrigued, I decided to give the stereo amp, the 710, a listen, which is what I've been doing over the past two or three months. (I now also have Soulution's 740 CD player and am expecting its 720 preamp this week or next.)
Since I'll be spilling the beans about this amp in my review of the MartinLogan CLX (in Issue 190), I might as well just say it here: This is the most transparent transistor amplifier I've yet heard. It is to amplifiers precisely what the CLX itself is to transducers--a paragon of fidelity to sources. Unlike the CLX, however, it is not limited in the low end or in ultimate dynamic range. It does what MartinLogan's great loudspeaker does everywhere. It doesn't sound darkish and liquid like an MBL or a LAMM amp and it doesn't sound whitish and brightish like a Spectral or a Boulder. It just doesn't sound. I've never heard a solid-state amp like it, and I've heard a few. In fact, I've never heard an amp like it. It is so delicately detailed that it can rightly be compared with the very best tubes, and yet it has no tube colorations. It is so fast and clear and unlimited in extension that it can rightly be compared with the very best solid-state, and yet it has not a trace of astingency or grain or bottom-heaviness or top-tippiness. It is the first solid-state amp I've ever heard that has made me rethink my bias toward glass audio. It's so damn realistic (provided, of course, that the recording is realistic).
While I'm not ready to give up tubes quite yet, I'm not willing to give up the Soulution 710 either, which is just a new kind of animal I've never heard before. The only other time I've had an experience like this one was when I first heard the belt-drive Burmester CD player about ten or twelve years ago, which didn't sound like any other CD player I'd ever listened to and opened up a whole new realm of possiblities. That's what this amp does.
I wish I could tell you I knew why the Soulution 710 sounds the way it does (or rather doesn't sound the way other amps sound). But I don't know why. Look at its site and you'll find a good deal about DC to 1MHz bandwidth, short signal paths, error amplifiers, fixed-gain buffers, and current amps with a potential of 200 amp outputs. Some of it is familiar and some of it is mind-boggling. All of its bespeaks a fanatical attentiveness to every element of design. Soulution's motto is: "Do not add anything, do not omit anything." I'd say it has come close to making that something more than an advertising slogan.
I've been quite irritated by certain other reviewers proclaiming that the sound of Product X or Y can't be described because it has no signature that the reviewer recognizes (i.e., it doesn't sound like anything else that came before it). Every product has a signature, but I'll be damned if I've got a handle on the 710's yet. I'll work it out over the next few months of listening, but for the time being the best I can do is tell you that it simply sounds like what it is amplifying--like what comes ahead of it, good, bad, or in between. Through things that are themsleves as transparent as the CLX and the AAS Gabriel/Da Vinci 'table with Da Vinci Grandeeza tonearm and Da Vinci Grandeeza cartridge and Audio Tekne phonostage, it is like peering over the shoulder of the mastering engineer.