Ayre Acoustics AX-5 integrated amplifier Follow-Up October 2014

Jim Austin wrote about the AX-5 in October 2014 (Vol.37 No.10):

These days, many audiophiles seem to prefer tube amplification to transistors. That was my impression as I prepared to write this review, and some informal research confirmed it: Most of the audiophiles I asked, in person and online, believe that music reproduced by a good tube amp has more heft, more texture, more blood. Transistors may amplify with less distortion, reproducing what's on the recording with greater fidelity, but tubes seem to more consistently facilitate an emotional connection with the music.

Why, then, are so many high-end transistor amps still being made? There are multiple answers: Tubes are a pain. They run hot. Transformers can be noisy. Tube amps can be unreliable. Worst of all, at least to me, is tubes' inevitable degradation over time. A transistor amp may sound different at different times of day, and when it's fully warmed up vs when it isn't, but any long-term decline in its sound is slow enough not to matter.

Tubes are a different story: I'm pretty sure that, a month from now, my tube amp won't sound as good as it does today. The difference may be negligible, and I'm unlikely to notice it day to day, but that is, precisely, the problem: It's insidious. Eventually, I'll buy new tubes, install them, and hope that I'm then back where I began—or even a bit ahead. Those days can be exciting and fun. And then the process starts over again.

This conjures up visions of the holy grail of amplification: a solid-state amplifier with all the advantages of transistors—reliability and ample current delivery—and the sonic immediacy, texture, corporeality, and blood of tubes. If such an amp existed, would I consider buying one? I would.

Also, I'm a big fan of integrated amps. While a poor choice for a reviewer—if your reference amplification is an integrated, you can't easily review separate preamplifiers and power amps—integrateds make a lot of sense for everyone else: Why not let the designer decide how to link the preamp and power-amp stages, instead of playing around with expensive interconnects?

Enter Ayre Acoustics' AX-5 integrated amplifier ($9950), which Art Dudley reviewed in the August 2013 issue. The solid-state AX-5 seems a good candidate as a replacement for a tube amp. It combines innovation—most notably, the substitution of variable gain for the usual approach of fixed gain plus attenuation—with a simple circuit (both old and new) and no global negative feedback. Its circuitry is also fully balanced—a significant advantage in systems that can take advantage of it.

I like a minimalist aesthetic, and the AX-5 is, as the British writers say, a lovely piece of kit. Its front panel has just two pushbuttons and two large knobs, one of each pair symmetrically placed to either side of the digital display. But the pushbuttons are flush with the faceplate even when fully extended—if you have big fingers, they aren't easy to engage. Except for the initial setup, which seems to require using the front panel, it's probably better to operate the AX-5 using its excellent, well-made, well-laid-out remote control.

A low-power-consumption mode lets you keep the AX-5 powered up without wasting electricity or generating too much heat. Most owners will probably use this mode as a power button, saving the main power switch on the rear panel for extended outages. But in low-power mode, it's possible to inadvertently engage the Mute function via the remote. When you power back up, there is, mysteriously, no sound; the only indication that the AX-5 is muted is some subtle dots on the display. You'll need to decide for yourself how much such things matter.

The AX-5 has some other quirks that, while not flaws, limit its versatility. Its speaker-wire terminals are extraordinary, the most impressive I've seen—just don't try to use them with banana plugs. Drilled through the review sample's massive terminal posts were banana-plug–sized holes. But I could never get a good connection with bananas: no sound in the left channel. With proper spades, though, these terminals made possible extremely tight connections.

The AX-5 is fully balanced, so of course its rear panel emphasizes balanced connection via XLRs. It has only two single-ended RCA inputs; if you need to run more than two components that require single-ended connection, the AX-5 isn't your best choice.

I listened to the AX-5 with Ayre's excellent CX-7eMP CD player (via a balanced connection) and an old-school analog front end: a Thorens TD-124 Mk.1 turntable on a slate plinth made by Oswalds Mill Audio, alternating between an Ortofon 90th Anniversary SPU cartridge mounted in a rebuilt (by me) Ortofon RMG-212 tonearm and an EMT XSD-15 cartridge in a Thomas Schick tonearm. Phono preamplification was handled by an E.A.R. EAR 834P phono preamp. For the SPU, I substituted for the EAR's internal transformer an Auditorium23 step-up transformer tuned to the SPU. Speakers were DeVore Fidelity Gibbon Nines. Balanced interconnects were by Mogami; unbalanced interconnects and speaker cables were from the Chord Company.

The first thing I noticed about the AX-5 was a mechanical noise when I changed the volume—a hollow, metallic scraping sound. True, this was audible only when the music was off or soft, but it was nonetheless an ugly sound, and out of place in a fine audio component. I never quite got used to it.

The AX-5 sounded superb: immediate and full, with much (but not all) of the richness, texture, and corporeality I associate with a good tube amp. The sound in the upper midrange and lower high frequencies was more pristine than I'm used to. Whether the source was vinyl or the Ayre CD player, I heard rich, warm, round, detailed sound with plenty of thereness. Compared to my tube integrated, the Ayre gave up a tiny bit of earth and gained a little bit of heaven. This was really outstanding sound that I could live with forever.

As I wrote in my review of the Marantz SA8001 SACD/CD player, in the October 2007 issue, I believe that a component should reflect its owner's values and fit the way its owner lives. In fact, I can't see how it could be otherwise. The Ayre AX-5 is less successful on this score than it is sonically.

After several weeks with the AX-5 in my system, Ayre Acoustics called to ask me to return the review sample. I packed it up and reinstated my regular integrated amplifier—a Leben Hi-Fi CS600, all-tube and wired point-to-point. When I hit the Power rocker, there was a mechanical thump and audible transformer hum. This was new. After a short e-mail exchange with Leben's US distributor, it was decided that I had a bad power tube. I dug out from my closet some "winged-C" EL34s, unscrewed the Leben's top panel, and soon was listening to music again. But those pesky tubes!—Jim Austin

Ayre Acoustics, Inc.
2300-B Central Avenue
Boulder, CO 80301
(303) 442-7300

tmsorosk's picture

Great review art .

Et Quelle's picture

The AX-5 is too rich for my blood. Shipping is undoubtedly free though any
extras would put you over the 5 figure price barrier.
The diamond cut circle is simple but not the best things. Superficial looks
mean the most in audio only. A 46 step volume system and Shallco switches, I guess justify Ayre going higher than most of their other products. I sure hope Stereophile shows an opened pic of future amp and it has a huge transformer in it like that. I have a tube preamp and solid state amp on my wish list but meanwhile I will use my Nano phono preamp.
Great job on the configuration and the review. You wouldn't want to spend too long on something like that!

audiofrk's picture

So Art can I ask from what you remember from the AX-7 is the AX-5 a step up (same audio quality but more power) or a new league (sounds better than the AX-7)?