I use an 8 gig 3rd gen nano with Shure SE420's for on the go. Such big sound from such a little system. I have Grado 225's for home headphones. I am a headphone geek. Plan to get a micro headphone amp from Headroom soon. Highly recommend either of these phones. A little discomfort with both pair during long listens ( 2 hrs or more). Just have to overlook it because the sound is so utterly incredible.