Audio Research DAC1 D/A converter Review System
The DAC1 was auditioned with the VTL 225W Deluxe monoblocks driving Hales System Two Signature speakers with the Muse Model 18 subwoofer via 3' runs of bi-wired AudioQuest Dragon/Clear bi-wire speaker cable. The preamp was either an Audio Research SP-11 Mk.II or the passive EVS Stepped Attenuator, while interconnects were AudioQuest Lapis (preamp to power amps) and AudioQuest Diamond (processor to preamp). I drove the DAC1 with the Esoteric P-2 transport via Aural Symphonics Digital Standard or TARA Labs Digital Reference.
In a fortunate coincidence, I happened to get a Wadia WT-3200 transport (reviewed this issue) about the same time the DAC1 was delivered. The WT-3200 is one of the few transports to provide a glass fiber-optic output (the Barclay and the Wadia WT-2000 are the only other ones I'm aware of), allowing me to audition the DAC1 with both coaxial and glass optical input. This situation also gave me a chance to listen at length to the differences between coaxial and glass interfaces. The glass-fiber interface and its sonic characteristics are also described in the WT-3200 review elsewhere in this issue.
The dedicated listening room has a pair of Phantom Acoustics Shadows, an active low-frequency control system, in the corners behind the Hales Signatures. All AC power to the preamp and processors under audition was conditioned by a magazine-owned Tice Power Block and Titan. Levels were matched between processors under audition to within 0.2dB at 1kHz. Other digital processors available for comparison included the Meridian 203, Proceed PDP 2, Theta DSPro Basic, Wadia X-32, VTL D/A, and a Wadia 2000.Robert Harley