Quote: How long a time was there between the sample with the external DAC and without? You would need two iPods to be able to do direct A/B switching. Otherwise there would be problems with auditory memory. And if you didn't level match, that is going to throw things off too. Everyone around here seems stuck on sighted vs double blind tests, but direct switching and level matching is MUCH more important than going blind. I spent several days setting up a shootout between an iPod loaded with an AIFF file through line out and the original CD in a very good midrange CD player. I carefully balanced the line levels, because they weren't the same, and set up an A/B switch. Try as I might, I couldn't discern any difference at all between the iPod and the CD. I tried the same with headphone out, and I could hear a tiny difference. Unless the DAC is coloring the sound somehow, I don't see how an iPod can sound any better than the original CD playing in a good standalone CD player.