RMAF 2011

I review Empirical Audio's pricey Off-Ramp 4 asynchronous USB–AES/EBU converter with its Monolith 1 battery supply in the forthcoming December issue and was impressed by the quality of its engineering as well as by its sound quality. At RMAF, Empirical's Steve Nugent showed me the Overdrive Ultra D/A converter ($10,000–$15,000), housed in a bronze case, which is well-damped. The DAC uses the Off-Ramp 4 circuit as its USB front-end and features just one analog stage following the I/V converter. Unusually, this uses a bipolar emitter follower instead of the common FET buffer. The digital circuitry is powered from the Monolith, feeding 12 Hynes-type regulators, though Steve Nugent feels that the analog stage sounds better when powered from a conventional AC-derived supply. The volume control in the DAC is elegant in that it reduces the reference voltage to the DAC chip, thus maintaining full digital resolution. There are two choices for full-scale output voltage.

Colorado Springs retailer Audio Limits was filling one of the very large ground-floor rooms at RMAF with sound, courtesy of the massive Venture Grand Ultimate loudspeakers ($90,000/pair) driven by the new AMP M1 solid-state monoblock amplifiers from BMC ($7790 each, $15,580 pair). Source was the BMC BDCD1 belt-drive CD transport ($5990), the BMC DAC1 Pre (HR) D/A converter/preamplifier ($6290), with Silversmith The Silver interconnects and speaker cables, Stage III power cables, and Weizhi PRS-6 power distributor.

I listened to a track I haven't heard in years in this room, Michel Jonasz's "Les temps passeé," from the CD La fabuleuse histoire de mister swing (1987), and was blown away by the enormous sound, the huge dome of ambience that was defined between and behind the speakers, and the sheer effortlessness with which the music was presented.

Taking an imaginative approach to the design of their room, rack manufacturer Dynamic Contrasts was holding the impressive BMC C1 integrated amplifier and the Esoteric UX-3SE CD player in a tight embrace with its RTS system. With Legacy Focus SE speakers, the sound in this room featured impressive dynamics and extension at both ends of the spectrum, but the sound was so loud, not only with David Essex's driving "Rock On" but also with 10cc's gentle "I'm Not In Love," that I couldn't stay. Perhaps I am just getting old.

Speaker engineer Don Keele almost wrote the book on measuring speakers. so when I bumped into him at RMAF and he told me he had a new speaker on show, I went straight to his room. There, I saw and heard the CBT36, which as you can see, is very unusual in both appearance and design. CBT stands for Constant Beamwidth Transducer and is based on unclassified military underwater sound beam-forming research. There are 72 0.75" tweeters crossed over to 18 3.5" Dayton Audio midrange units, arranged in groups that, with the 36° arc of the 5'-tall array, gives sound that doesn't change its balance as the listener sits or stands. And as you can see from the mirror that Don has slipped in front of the speaker in my photo, the ground-plane reflection of the array effectively doubles its height.

Stephen Mejias has already reported on the sound in the room shared by Wilson, Transparent, and Dan D'Agostino. I was equally impressed, agreeing with Millennia Media's John La Grou that one of Peter McGrath's classical recordings, Mahler's Symphony 5 performed by the New World Symphony under Michael Tilson-Thomas and captured with Joe Grado's omnidirectional microphones, was as good as it can get when it comes to two-channel representations of an orchestra. (John manufactures the very-low-noise mike preamps I use for my Stereophile recordings.) But I really just wanted to show another picture of the forthcoming Dan D'Agostino Momentum line preamplifier, with Dan's wife Petra lending me her hand for scale, as she rotates the volume control ring around the meter.

Avatar Acoustics’ Darren Censullo always puts together an impressive system. Every aspect seems carefully considered, made to complement the whole.