I should add, no iem had a treble bump in ios6 either. Ios6 had an edge, typical of all solid state gear, in the treble region. This is what ios7 fixed. As a long time iPhone/apple owner, it's quite a welcome change.
To me the ios7 is both cleaner and smoother. Didn't think software could make a difference but now I believe it does not because of iso7 but Amarra (which is a music software that puts iTunes to shame).