I've long been skeptical about claims made for digital front ends, on
the basis that I've never been able to tell the slightest lick of
difference between any device that's higher quality than a
PlayStation. But reviews for the DAC-1 were positive, and it didn't
have the sound of snake oil, so I figured I'd give 'er a whirl.

My system is a Slim Devices Squeezebox (playing WMA Lossless streamed
as PCM) to a Parasound P/LD-2000 preamp, Parasound HCA-1500 amp, and
Paradigm Studio 100 speakers. I hooked the DAC-1 to the Squeezebox's
coax digital out and into the preamp, set it to "Variable" mode,
adjusted its volume until the two sounded like they were the same, and
commenced non-blind A/B testing.

Result: I couldn't tell a goddamn bit of difference. The
Squeezebox's analog outs sounded precisely identical to the digital
out going through the DAC-1. If it weren't for the click of the input
switching, I wouldn't have even known there was a switch being made.

--
Mike Kozlowski
http://www.klio.org/mlk/