Solid State Power Amp Reviews

Overall, however, it was the palpability of the Ayres' sound that most impressed me. (I wonder if this is what Art Dudley means when he discusses components having "flow," the individual acoustic objects within a mix clearly existing separately from the overall image.) I have mentioned before the problems I had mixing the Jerome Harris Quintet's Rendezvous (CD, Stereophile STPH013-2; out of print, though one track is still available on our Editor's Choice CD, STPH016-2). Jerome's Taylor acoustic bass guitar has a distinctive tone and a somewhat soft sound—but if I brought its level up too much in the mix, it began to compete with rather than reinforce the solo instruments. Long after the CD had been released and memories of the post production had dissipated, I attempted to remix the album from fresh. Comparing the new mix with the original, the balance of Jerome's bass was virtually identical. It is what it is, and through the better audio components, the level of the bass guitar does indeed sound musically appropriate. More significant, with the Ayre amplifiers, not only was the bass's image clearly defined, that image seemed more palpable than I usually hear, separated to a greater degree than usual from the other instruments playing, and eliminating the potential problem with the mix.

If I'm going to talk bass guitarists, I mustn't forget the late Jaco Pastorius. When he launches "Cotton Avenue," from Joni Mitchell's Don Juan's Reckless Daughter (AIFF file, 24-bit/192kHz needle drop from LP, Asylum K63003), his detuned low F and C were so well formed and so palpable that they rolled from the speakers and across the floor toward me!

This palpability made itself felt even with historic recordings, such as the Grateful Dead's Live Dead, from 1969 (ALAC files ripped from CD, Warner Bros. 1830-2), with its superlative sequence of "Dark Star," "Saint Stephen," and "The Eleven." And it's not coincidental that I'd been listening to Sly and the Family Stone's Live at the Fillmore East: October 4th & 5th, 1968 (4 CDs, Epic 88843023712) through the Ayre-founded system when I recommended to music editor Robert Baird that we make this almost-half-century-old set this issue's "Recording of the Month." In contrast to the Dead's Phil Lesh, who often plays around the beat, adding counterpoint to the drum lines, the kick drum and Fender Jazz Bass of the Family Stone's Gregg Errico and Larry Graham respectively march in lockstep through these high-energy concerts, together in time but distinguished in tonality by the Ayre amps. Lesh and Graham are polar opposites in their approaches to the music they play, but with all of the speakers I used with the Ayres during the review period, both bassists were equally well served, the MX-R Twenty combining power with sweetness.

Classical double bassists were served equally well by the Ayre MX-R Twenty. I used to love the music of Sibelius, but hadn't played any for too long a time. I reached for Symphony 5, with Herbert von Karajan conducting the Berlin Philharmonic (ALAC files ripped from CD, EMI Studio CDM 7 69244 2). To underpin the work's ambiguous tonality, halfway through the finale Sibelius has the double basses, normally used by composers to provide a solid foundation to the harmony taking place above, playing divisi two notes that "fight," E-flat and F. With regular systems, the listener is aware that there is something "sour" in the apparently muddy sound of the basses at this point; a look at the score reveals why. With high-quality speakers driven by the MX-R Twentys, the score is unnecessary—you hear the discord as Sibelius intended: two low notes almost identical in frequency, but far enough apart in pitch to be easily distinguished, and understood as deliberately intended by the composer.

Comparisons
The Pass Labs XA60.5s have been my go-to amplifiers since I reviewed them for the January 2014 issue, primarily because of the spatial magic they work. The soundstage thrown by the Ayre MX-R Twentys was more forward than that produced by the Passes, with foreground objects lying more in the plane of the speakers. In that aspect of their sound, the MX-R Twentys reminded me of Lamm Industries' M1.2 References, whose sound has a similar glow. But the MX-R Twenty's lows were fuller than the Lamm's, and, especially, better controlled and more weighty than the Pass's.

Of the amplifiers I had to hand, the champ at controlling woofers was the MBL Corona C15. With levels matched to within 0.1dB, the MBL's reproduction of my solo Fender Bass tracks on Editor's Choice (ALAC files ripped from CD) sounded tighter but more ethereal than the Ayre's. We're back to that palpability thing. Both amplifiers gave an almost perfect combination of leading-edge definition and tonal weight, but the Ayres made my Fender sound—and feel—more as if it were in my hands.

Compared with the Bricasti M28 monoblocks—which, at $30,000/pair, compete almost head-on with the Ayres in price—the MX-R Twentys did lack ultimate low-frequency extension. As I write in my Follow-Up review elsewhere in this issue, the bass guitar and kick drum in "My Rival," from Steely Dan's Gaucho (24/96 ALAC file transcoded from FLAC, MCA/HDtracks B0000868-36), sounded weightier through the Bricastis than through the Ayres. But the M28 has a more polite upper-frequency balance than the MX-R Twenty.

Conclusions
For an amplifier at any price to be able to do everything superlatively well is a big ask. But as I finish writing these words, I'm listening to Bill Frisell's rhapsodic traversal of "Shenandoah," from his East/West (ALAC files ripped from CD, Elektra Nonesuch), with GamuT RS7 speakers (review forthcoming) driven by the Ayre MX-R Twenty amplifiers. The jump factor of Kenny Wollesen's snare drum, the growling palpability of Viktor Krauss's double bass, the sense of space surrounding Frisell's stereo-processed guitar, the sheer musical communication—it's hard to envisage how another amplifier could do better than this.

But this performance comes at a price—the Twenty costs nearly 80% more than the original MX-R. Still, it's fair to say that two of the three amplifiers I've tried that get closest in overall sound quality to the Twenty, Lamm's M1.2 Reference and MBL's Corona C15, aren't that much less expensive—and the third, Bricasti's M28, costs slightly more.

All I can say is that if fortune has smiled sufficiently kindly on you that you can write a check for a pair of MX-R Twenty amplifiers without breaking a sweat, you should do so—and then invite me round for regular listens.