I tested the Benchmark ADC against RME (ADI-8 DS) and Apogee (Rosetta 800).
RME at first seems have quite a netutral sound quality to it and nice technical specs when measuring, but has some minor unwanted coloration in the upper bass. It also exhibits a less than perfect ability to clip (if you're into that), adding a bit of unwanted distortion. The stereo image seems wide but I'm getting a bit worried about the apparent phase-correctness, although I cannot measure anything. I currentlu have RME ADI-8 DS but about get a 2 ch. ADC.
Apogee Rosetta 800 has a slightly "warmer" sound for lack of a better word. It did feature a very small amount DC offset and what appeared to be a very small loss of RMS to peak (.3 dB) compared to both RME and Benchmark. The very low end and very high end has the most info compared to the other converters. However that's exactly the kind of coloration I don't like as it seems to be slightly hyped and "hi-fi"ish. I returned the Apogee.
Benchmark ADC seems to have a wider stereo image, more detailed and crisp high end. Tighter low end. Sounds nothing like either the RME or Apogee, quite different. When measured it had absolutely perfect specs. The sound is the most pleasing to my ears, somehow it sounds just right, and unlike RME the stereo image is not phasey, and unlike Apogee the low and high end is not hyped. I'm keeping the Benchmark to compare it with Lavry Blue.
Hope that might help.
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