Being a (non-professional) recording engineer -- my specialities are the recording of organ music and chamber music-- I required next to my Sennheiser HD 595 (excellent!!!) a pair of closed headphones. These would be useful in the case that the recording equipment lives in the same room as where the music is made. Attracted by Koss'reputation and good reviews I decided for the Pro4AAT. At first I conected the headphone to the output of my computer's sound board, and it became clear that this output is not capable of driving a high-impedance...