Isn't thread drift wonderful?
All DACs don't sound alike, but they should. Seriously. A DAC is a source. Its job, its only job, is to convert digital data to an analog waveform that looks exactly like the analog waveform that was originally converted to digital data. It shouldn't have an analog output stage designed to be a tone control that attempts to make the resulting signal sound warmer, or more "musical" or, God forbid, more analog. It should be transparent. And it is all based on a pretty mature technology that has reached the point where most competently-executed DACs that are not deliberately attempting to change the tone will sound very much alike. If you're hearing clearly audible differences between a Benchmark, Lavry and Apogee (three of many competently-executed examples) you may be the one hearing what you read -- what you read on audiophile web sites -- or you may be hearing something amiss.
With that said, there are many "high-end" DACs that sound different, but they do so deliberately, and typically in the analog output stage. Are they wrong? Not if you like the sound better, but they are unquestionably less accurate than a properly-implemented Wolfson or Burr-Brown or whatever DAC chip with an output stage that simply and transparently brings the analog signal up to line level. And that's something you can find integrated into AV receivers at Best Buy.
Tim
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