I definitely dont have the most astute ear but as i listen more and more im learning a lot more about what to listen for, differences, etc. My current setup is digital out from my mac pro to a beresford dac and using the built in headphone amp to drive a pair of akg k701s. The more and more i listen, i feel like the amp is not giving near enough power to the akg's and im not getting the full sound they can produce. With that said, i tried plugging the headphones into a yamaha mid range home theater receiver playing a cd through a ps3 and noticed some interesting differences from the beresford with apple lossles. First thing i noticed with the yamaha was that the overall sound (soundstage?) was much more full and balanced and as I turned up the volume and I didnt feel like the highs were going to blow my ear drums out (sometimes feel this way with the beresford). Im guessing this is just an issue of providing more power although i still felt like the akg's have more in them if there was even more power. Second thing I noticed though was that the beresford seemed to produce much cleaner highs and mids. Im guessing that this is because of a higher quality signal/DAC in the beresford. Now the only thing that caught me here was then when I was comparing the 2 systems with "Us and Them" from Dark Side of the Moon, i could hear a few details with the Yamaha that were much harder to hear with the beresford. For example, there is a slight vibrato sound from the sax in the intro as its trailing off right before the vocals start (1:37 ish). I didnt have much trouble hearing it with the yamaha (in fact i never really noticed it with the other setup) but with the beresford, it was muffled and i really had to listen closely to hear it. Sorry for the long post but I guess what im wondering, is what are causing these differences and what would I need to get more out of these amazing headphones. Keep in mind that this is for my personal listening, not for mixing, recording, etc. Thanks!