By that you mean it's not as strong? [sorry bout my understanding].
The reason why I asked is because if I recall, the iPhone 5 have a output impedance of more than 1 Ohm so it will for sure weaken the bass and brighten the highs to my experience with my iNano 3rd and it goes extremely loud! If the iPhone 5s offer lighter bass on the XBA-4, I am guessing the output impedance is even higher. [The XBA-4's impedance at the lows is around 6Ohm if I remember]
Edited by BillsonChang007 - 9/21/13 at 3:21am