In many ways, the Art Audio Symphony II is a very different kind of amplifier when compared to that Opera Reference 9.9C. In other ways, it's surely cut from the same cloth. There's just no getting away from what makes the 300B such a wonderful and recognizable tube. The Symphony II shares the same illuminated musicality that I've come to associate with 300B amplifiers and it has the same kind of focus as well. It exhibits the same truth of instrumental timbre that instantly communicates the gestalt of real music. It's the kind of verisimilitude with reality that instantaneously correlates with real music at the cerebral level. Its absence or presence also largely contributes to listening fatigue or freedom from it. The more work the brain is forced to do by way of correlation playback to the real thing, the more immediate the satisfaction and the less the work-induced fatigue. It's what leads to all-day and well-into-the-night listening sessions that terminate only at the clock's (or wife's) demand. In short, call it easy listening. But don't confuse it with the artificial hyper-detailed minutiae propagated by some products and characterized by some listeners as HiFi.


Some of those artificially detailed systems achieve their sound with tipped-up trebles. Those sound more detailed initially as the tweeters call attention to themselves. Eventually and invariably, they become amusical and completely artificial. The same tweeters which originally seemed to allow you to hear deeper into the music proceed to now slice and dice it up into various components and, like all the King's horsemen and all the King's men, fail to put the music back together again.
I believe that what SET aficionados understand is that it is in the midrange where a system will be made or broken. Get the midrange right and, if need be, a multitude of isolated sins at the extremes can be forgiven. Not that the Symphony II is guilty of such sins. But boy does it ever get the midrange right.


Down low is where the Symphony II really begins to set itself apart from a lot of other tube amplifiers, high-powered or not. Here the Symphony manages to walk that fine line between warmth
and wooliness, heft and bloat like few others. With all the speakers at my disposal -- including some speakers that you wouldn't dream of pairing up permanently -- the Symphony impressed me with both its weight and control. Contrary to previous experience with 300Bs, this bass was perfectly married to the midrange, with a remarkably full-bodied upper bass and lower midrange transition.


Not that I was surprised; after all, the same can be said for the Art Audio Carissa. In my review of it, I mentioned how into highly efficient speakers, the Carissa actually sounds more powerful than some highly powerful solid-state amplifiers. While the Symphony II doesn't exhibit quite the same machismo, it's very solid and even more sonically neutral.
But it is at the other end of the sonic spectrum where the Symphony II bests every other amplifier I've ever used. To my ears and in my system, the Symphony II's treble response was practically perfect and beyond reproach. It's where the Symphony clearly outclasses my beloved Carissa. Clearly? Well (embarrassed cough), yes - clearly, importantly and yet subtly. With the Symphony in the system, I hear the kind of subtle shimmer and delicate detailing that I am suddenly aware is missing with the Carissa. Where the Symphony II renders delicate shadings with color, the Carissa seems to bleach those delicate colors just a bit. It's there and it's unmistakable. However and in fairness to my own amplifier, it's also the kind of thing that when I reinsert the Carissa, I only miss it for a few moments before I forget what I was listening for. In other words, if the Symphony II makes the Carissa sound as if it were in error, it's an error of omission - the easiest kind to live with. On the other hand, the Symphony II seems to exist to set that record straight. And does it ever.


Unlike a lot of speakers with advanced tweeters that are highly praised by some of the press only to sound unnaturally present to my ears (if you can hear a tweeter, there's something
wrong), the Symphony II's treble performance is one of perfect balance. It makes its presence known with subtle nuance rather than being overtly spectacular. There's no edge, no excess prominence, just a refinement and musicality that I haven't heard from many other amplifiers if any at all.


In terms of drive, the Symphony II is all Art Audio. Readers would call me nuts if they knew exactly how much time the Symphony II spent driving a pair of 4-ohm (3.3 ohm minimum) 87dB Thiel PCS monitors in for review. The same readers wouldn't believe their ears once they heard how well the Symphony II's 10 watts drove them. In fact, though the bulk of my time shared with the Symphony II saw it mated to the Third Rethms, it was the nature of the Rethms' limited bandwidth that really failed to communicate many of the Symphony II's extraordinary traits. Despite a marvelous midband but with no bass and only shelved-off highs, the Rethms only hinted to me that the Symphony II was a special amplifier. It was on a lark when I placed the Thiels in the system only to feel that now I was getting the full measure of the Symphony II. (Readers may remember how I sheepishly mated the Magnepan MG 1.6QR to the Carissa only to arrive at surprising success as well.)
In concert with the Thiels' tweeter which is both extended and extremely revealing, all I got was smoothly flowing treble magic. Magic? Yes, magic. I'm fairly partial to treble that is sweeter than it is forward and have been known to gravitate toward a treble presentation that maybe trades off some extension and detail for one with less of a chance to expose warts that are more gracefully overlooked by more forgiving tweeters such as in the Silverline Sonata Mk II. But with the Symphony II and the Thiels, I felt as though I could finally have my cake and eat it, too. Eve Cassidy's Live at Blues Alley [G2-10046] is a small Blues club recording that is blessed with a plethora of percussion instruments including quite a variety of cymbals showcasing a varied palette of tonal signatures and varied sustains. The Symphony II not only
gave me greater and more saturated variations of those shadings and greater differentiation of the subtly different attack/decay signatures but it managed to give them a touch greater presence without thrusting them too forward in the mix. In other words, they were there to be savored without being given supernatural presence.


Completely surprising to me even after several months of cohabitation was the way this amplifier combined with the little Thiels for a stunning rendition of the various bass instruments. The little Thiels do a really good job with the bass and, in small to medium-sized rooms, will surprise with perceived bass depth and authority. The Symphony II did a phenomenal job of taking hold of the little woofers for bass lines that were not only properly weighty but more musically detailed than I would have predicted no matter the power rating of the amplifier in question. Bass was powerful, even and insightful - almost shockingly so given the Symphony's meager 10-watt output.


No question, the Symphony II gave arresting performance at both ends of the spectrum but its rendering of Cassidy's voice was the reason I kept coming back to that disc over and over again. For a start, her voice was reproduced with creamy smoothness. Again, there was musically significant insight, detail and nuance aplenty as her voice was suspended in 3-dimensional space surrounded by cubits of air. I've listened to this disc many times with many components and never before was it reproduced with such vivid transparency. It was truly as if the CD had finally broken in!
Another disc that I've been playing a lot of late is Dire Straits On Every Street [Warner 9 26680-2]. Its tapestries of sound more complex than the simpler jazz composition on the Cassidy disc were reproduced with gorgeous appeal. Knopfler's voice had vivid authenticity that was never in question. Soundstaging on both "Fade To Black" and "You and Your Friends" was holographic and vivid to equal degrees, with cleanly rendered guitars beyond the speakers which had vanished without a trace. Where the Symphony II surprised was on "My Parties" where volume levels averaged mid 80s. Once again, I almost couldn't believe the drive this little 10-watt SET was putting out into the formidable Thiels. I was obviously careful not to push macro dynamics and ultimate SPLs but was able to achieve my usual volume levels on all Jazz and most Pop and Rock music without any audible forms of compression or other signs of distress.


Some Absolute Heresy on Bass
You know, there's more than one way to skin a cat or to cobble together a system. While reviewing the Third Rethm speakers, I spent a lot of time using various subwoofers with beguiling success. The Symphony II was the primary amplifier used and every sub was fed a high-level signal. In other words, the subwoofer signal, via speaker cable connections, came directly from the Symphony II. While not strictly used to drive the subwoofer (the high-level signal would be stepped down via a Z-coupler for the subs' internal amplifiers), it was directly responsible for the quality of the subwoofer's input signal. I found out early on that this was a superb arrangement with the Rethms which produce no bass of their own. It worked so well that I tried it again on speakers that required a bit more bass support from the Symphony II. I wanted to discover if the Symphony kept its bass composure when forced to work a little harder.


I used the inexpensive Axiom M3ti and a pair of Velodyne SPL 800 subwoofers for this experiment. The diminutive Axioms are rated at 92dB (88 anechoic), which would tax the Symphony considerably more than the 100dB Rethms did. As before, I wired the Velodynes to the Symphony II's speaker outputs. What happened almost blew my mind.
First, I wasn't prepared for just how good the little Axioms could sound with a first-class amplifier. They have always been a clearly articulate speaker that lacked some of the smooth musicality that, generally speaking, better and more expensive speakers bring to the table. But the Symphony II just filled in all the blanks and these Axioms suddenly sounded rounder, smoother and more aflow. Imaging, always very good with the Axioms, now became much more palpable and 3-dimensional. The Axioms' Achilles heel has always been its tweeter which (though good for its class) doesn't match the finesse of the midrange particularly when pushed. Well, the Symphony II's outstanding treble wasn't lost on the Axioms. I was shocked to find out just how good the tweeter could sound. [John's "put the money before the speaker" experiment here eerily mirrors my own recent one wherein the mighty Avantgarde Duos were replaced by the far more affordable Gallo Reference 3s without signaling any significant collapse or compromise - Ed.]


Getting back to the bass, when I put on Peter Gabriel's Security [Geffen 2011-2] and cranked the volume more than just a bit, the CD just exploded to life. In addition to the way the Axioms did their best to rise to the occasion, the Velodynes sounded fast, clean and solid. Songs like "I Have the Touch" and "Shock the Monkey" are propelled by strong visceral (often synthetic) bass lines and strong and visceral is exactly what I heard. "Wallflower" and "Kiss of Life" supplied opportunity for the Axioms to throw up a kaleidoscope of colors and images and they performed their part really well.


I'm more and more aware of small speaker systems such as Combak's Bravo or Omega's little Grande loudspeakers (just to name two) that are easy to drive and, with the use of a good little subwoofer, can make for relatively inexpensive and highly compact systems. It occurs to me that the way the Symphony II drives such speakers while simultaneously providing a coherent bass signal to a small powered subwoofer seems like a really smart way to go in a lot of situations. Of course as was the case with the Axioms, if you own small and inexpensive yet solidly designed speakers, you may be shocked at just how good they can sound on their own with something as accomplished as the Symphony II at the helm.


Conclusion
It should be obvious that the Art Audio Symphony II does not sound like solid-state. Is it perfect? Of course not. No matter how overachieving for its size, Art Audio's Joe Fratus insists that the Symphony II really does conjure up only 10 watts of power per channel. This necessarily limits its appeal to those with small rooms or fairly high-sensitivity speakers. I've thus far also failed to mention one nagging ergonomic design flaw of the Symphony - its on/off switch. It's located on the amplifier's back right between the heat sinks that dissipate heat from the voltage regulators, and right next to the IEC power connection. Users will have to place the Symphony II on a top shelf to be able to reach over the amplifier's top to this switch. Powering it off after the tubes have heated up does require a bit of care. (Whew, I've been waiting for an opportune moment to get that off my chest!)
In the context of a low-powered SET amplifier, the Art Audio Symphony II amplifier is the most accomplished piece I've used to date. Within its power limitation and as used in my system, I have to conclude that the Symphony II is as near to perfection as I have encountered yet. I've heard and used a lot of amplifiers, many costing far more than what Art Audio is asking for the Symphony II. If it can be improved upon -- perhaps by more expensive amplifiers within the Art Audio line like the Diavolo, Jota or PX-25 -- I'd love to know how. It's subjectively very linear and neutral. It does marvelous things at the frequency extremes. It has the kind of midrange that audiophiles empty their savings
account for and exudes that SET magic that people who claim solid-state superiority may never understand. Its way with musical detail is absolutely mesmerizing as it seems to leave no stone unturned in its search for musical nuance yet remains the antithesis of a laboratory instrument. And when you consider the great packaging and high level of build quality, Art Audio sells it all at a very reasonable price.


This is the dreaded part of the review where I'm about to lament the fact that very soon, the man in brown will show up at my door to whisk away the Symphony II back to its proper home. But not today! Following my last-minute fact-check by phone, Art Audio's Joe Fratus promised to let me hold on to the Symphony II for a while longer to investigate the results of some tube rolling whereby I shall report back on the different signatures of certain available 300B options - the Sophia mesh-plate and the new KR 300B to be specific. So as they say, stay tuned but don't hold your breath - such investigations are not to be rushed but savored...!
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