Ayre Acoustics V-3 power amplifier Sam Tellig Comments
"It's nice that the Ayre V-3 amplifier sounds so tubelike, but why not just buy a tube amplifier?"
Charlie Hansen laughed.
"If you can put up with the high prices and maintenance of tube gear, then go for it. But most people don't want to put up with the expense or the idiosyncrasies of tubes.
"Look," Charlie continued, "great tube amps still have a little bit of midrange magic that no solid-state amp I have ever heard quite gets. But the V-3 does many things better than most tube amps do. It's more dynamic. Bass is more controlled and tuneful. There's more resolution.
"The idea is to make something great-sounding and reliable that people can afford. I personally like the sound we normally associate with tubes—relaxed, musical, lots of information, but not presented in any kind of artificial way. I think that sound is truer to the music and lets you understand what an artist is trying to convey.
"The problem is that tubes are expensive and unreliable, and it's hard to find good tubes. It's also expensive to make a tube amp, because you have to have output transformers, and good transformers are expensive."
"...a grand experiment in sleep deprivation"
I was talking to Charles Hansen, founder of Ayre Acoustics, and before that the founder of Avalon and designer of the Avalon Ascent and Eclipse loudspeakers. If he was in a merry mood, maybe it was because two weeks earlier his wife Colleen had given birth to their first child, an 8-lb 4-oz boy named Cooper Elliott Hansen. "I am currently living in what feels like a grand experiment in sleep deprivation," said Charlie.
The Ayre V-3 is another of Charlie's children, and if ever an amp was aptly named, it's the Ayre. Taking a cue from Naim Audio, which is "name" by another "naim," Ayre means to suggest that its amplifier (and, presumably, other products to come) excels at spatial resolution—the sense of air...or "there" there. Solid-state amps rarely do spatial resolution as well as tube amps do. The Ayre V-3 is one of the few notable exceptions.
A handsome amp, and well-built, too—look at that ½"-thick faceplate—the Ayre V-3 is reasonably compact, so you can set it on a table out of the way of kids or pets. Properly ventilated, it can go on or in an equipment rack—no need to place it on the floor. One person can actually lift and move it—unusual for a high-end solid-state amplifier.
The amp has what look to be two on/off switches, one each on front and back. Uh-huh—the switch on the back is the actual on/off switch, the front toggle switch is a standby switch. Flip it down and it'll turn off the power to the output transistors—handy if you want to change cables, etc. But otherwise, says Charlie, leave it on all the time (footnote 1).
Parts quality is high, including very sturdy speaker binding posts on back—none of those damned plastic binding posts (there shouldn't be any of those in a $3450 amp anyway). The design is fully balanced from output to input, the balanced design helping to reduce noise through common-mode rejection. (There are also input jacks for single-ended RCA cables.) I used the Ayre with an AudioPrism Mantissa line-stage and a Passion passive preamp. CD sources included Meridian 508 and Krell KPS-20i CD players. Unfortunately, I didn't have a balanced preamp on hand at the time of auditioning.
There is no loop feedback around the output stage, just a little feedback to the driver stage, necessary to control DC. I asked Charlie how he can get away with this and still keep the output impedance suitably low—around 0.25 ohms.
"I was hoping you'd ask. It's because we use very-high-transconductance MOSFETs, which were developed, actually, for low-loss switching in electric cars. The higher the transconductance, the lower your output impedance." The amp uses two pairs of these high-transconductance MOSFETs per channel—this being a balanced design, each pair of devices is carefully matched, as indeed are other parts in the signal path.
Valvophiles widely believe that one reason tube amps generally sound as good as they do is that they tend to use little or even no loop negative feedback. Indeed, the few times I've been able to dial-in feedback—with the Manley SE/PP 300B monoblocks, for instance—I've been able to hear the sound quality deteriorate. What does feedback do? If overused, it destroys the palpability of images, robs an amp of harmonic richness, and removes ambient information—that's right, air...or Ayre.
Tighten up that bottom end!
Feedback can, however, tighten up the bass, make it less loosey-goosey, and give an amp that crisp, even sterile quality that many audiophiles apparently like (footnote 2). It also lowers an amp's output impedance—desirable insofar as the amp's frequency response will remain constant regardless of speaker load.
The Ayre is also unusual in that it uses what Charlie calls a "two-stage power supply": inductors in the first stage (ie, a choke), capacitors in the second. According to Charlie, the inductors act as power-supply filters, storing energy in their magnetic fields and releasing that energy slowly to the capacitors so there is continuous current. Charlie says this eliminates the noise caused by high-current charging pulses—sort of a rat-a-tat-tat.
Ah, the good old days...
Before 1950, everyone used inductors in their power supplies. As filter caps improved, packing more capacitance into the same physical space, designers abandoned inductors in the power supply. But, as so often happens in hi-fi, perhaps such "progress" wasn't. Inductors are useful. They act as low-pass filters. They store energy. They resist the change of current through them. Put them ahead of capacitors and capacitors can recharge more slowly.
Footnote 1: That is, if you want to draw 210W in operating mode, no signal, or 65W in standby mode at all times—this according to the operating manual. The Ayre V-3 is heavily biased into class-A and generates considerable room heat of its own, as I found out. The prospective owner should factor in the cost of keeping the amp powered—it could cost you more than replacing tubes.—ST
Footnote 2: Music lovers do suffer at the hands—or ears—of audiophiles.—ST