Audacious Audio

It was almost seven years ago that Nelson Pass, whose talks and exhibits I'd covered at many a Bay Area Burning Amp DIY event and audio show, surprised me with a loan of two Pass Laboratories' XA 160.5 class-A monoblock amplifiers. Ten months later, after I'd commented that my system had challenged the XA 160.5s in the bass department, he sent me a pair of XA200.5 monos. I connected those bigger babies to Wilson Audio Sophia 3 loudspeakers and some now-discontinued digital components with Nordost Odin 1 interconnects and speaker cables. Then came my way, toward the end of 2016, the XA200.8 monoblocks ($42,000/pair).

Whereas the Pass Labs preamplifiers are designed by Wayne Colburn, the power amplifiers are the work of company founder and high-end audio veteran Nelson Pass, who even lays out his own circuit boards. The X-model amplifiers, beginning with the X1000 in 1998, were the first implementation of Nelson Pass's patented Supersymmetry topology (see "Nelson Pass on the Patents of Pass"). The XA series, which debuted in 2002, combined Supersymmetry with the single-ended class-A operation of the Aleph series. The XA.5 models offer detail improvements over the XAs.

Playback Designs was founded less than three years ago. However, with the release in 2008 of its MPS-5 Music Playback System—a slim, full-featured SACD/CD player and DAC that costs $15,000 and is built in the US—the company has since established itself as a significant player in high-performance digital audio.

I think I've finally figured out the secret of Stereophile's success. You, cherished reader, don't read this mag because it's chock full o' reviews of tantalizing audio gear (even though it is). And you don't read this mag because JA and RL strive so hard to keep the literary quotient as hi as the fi (even though they do). And I know you don't read this mag cuz trusting yer own sensory input is a mighty scary proposition indeed so you look to Stereophile as to a Holy Bible that eases your Earthly burden by telling you, Ah say Ah say TAILING YEW what to buy (do you?).

Powerful, massive, and expensive, Revel's Ultima Rhythm2 subwoofer ($10,000) swept me off my feet when I first saw it in Harman International's suite at the 2013 Consumer Electronics Show. It outsizes, by 49 lbs and 2.6 cubic feet, Revel's previous flagship model, the Ultima Sub30, which I reviewed in the November 2004 issue. Its specs read like no other sub's: 196 lbs; 18" cast-frame woofer; dual 4" voice-coils; 4kW peak power from twin internal amplifiers that generate 1kW RMS; 115dB peak acoustic output; a fully configurable, high-resolution, 10-band parametric equalizer (PEQ); an internal crossover with high- and low-pass outputs; and PC-based setup via USB. The Rhythm2's patent-pending design is said to let just enough air move in and out of the cabinet to prevent any distortion-inducing pressure due to heating of the voice-coils. And its veneer, shape, beveled top edges, and bottom plinth exude the quality found in Revel's top-of-the-line floorstanding speaker, the Ultima Salon2, with which I was familiar.

Following my review of the floorstanding Magico S5 Mk.II last February, I spent some time with two-way stand-mounted speakers from Aerial Acoustics, Bowers & Wilkins, and Dynaudio. As much as I appreciated the small speakers' virtues, I found myself missing the big Magico's bass extension and ability to play loud; my next loudspeaker review, therefore, would be of another floorstander.

It's been a while since we published a review of a Rockport Technologies loudspeaker.