Been listening to headphones for 20 years had many settled on the Beyer T1 and the Senn hd600 the 600 were my first and after at least three pairs my last. With this amp DAC combo, I can say with confidence I am done and glad of it. The Sennheiser with balanced Cardas cable is awesome! I use the DAC-out on the XP to the beyer A20 and they have never sounded better. Very pleased camper here.