Just found out today the Audeze pads fit the Beyer T1 and T5p pretty well.
Much better comfort for both
Leather gives the T1 a midbass and bass boost (think dub step) while taking the edge off the treble peak of the T1. Air and detail remain albeit slightly softened. Essentially turns the T1 into a 'beats' loving headphone. Good for dub, rap, hip hop, etc.
Velour I haven't yet tried but I believe it will give a flatter response then the leather even greater comfort and retain more of the air and open feel the T1 are famous for.
Edited by groovyd - 10/26/14 at 6:30pm