darrenyeats wrote: > Archimago, > Ok, I now understand your criticism of Rockwell's analysis. Good point > well demonstrated. It explains the Sony. > > The Benchmark results with strong spurs across the whole spectra at > -60db, are still distinctly worse than the dirty one you just posted ... > plus Rockwell's (also dirty) spectra for the Apogee and Audioengine. > Could we infer that all were non-multiples and this BM difference is due > to poorer overshoot handling? > > The much bigger difference in the Sony spectrum and your better spectrum > would still be explained by the integer multiple (as well as potentially > better overshoot handling?) > > My point is, we know the DAC1 lacks DSP headroom (and the DAC2 has this > headroom) and I expect this is at least contributes to Rockwell's > particularly bad DAC1 spectra. > Darren > > > > Sent from my HTC Sensation Z710e using Tapatalk 2
Yes, that is exactly what I was trying to get at. It looks like ASRC caused the square wave spectrum to look distorted compared to the clean Sony. As you said, perhaps he's suggesting that lowering the volume will show a significant reduction in the amount of distortion but it's hard to tell from those graphs, especially the 2nd graph in that section since the text suggests there should have been another image if the mouse rolled over it. I'm also a little confused about the difference he's seeing between USB and TosLink (first roll-over graph). I would have thought that with the ASRC, the spectral difference would be minimal if even present. It also doesn't look like he's using Bit-Perfect with iTunes to ensure accuracy, furthermore I'm also a little concerned about his decision to use that "six-year-old Belkin 7-way powered USB hub with a 10-year-old, 6-foot USB cord" - nothing wrong if we know for sure this old setup isn't introducing its own noise into the mix (I've seen this kind of problem in tests). ------------------------------------------------------------------------ Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=98661 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
