Well I don't want to go off topic too much, but Tyll's review of the X2 on innerfidelity also pointed out grainy treble, that sometimes can become too hot. It was the case also with the Urbanite XL, despite having the same driver of the on-ear.
Our "problem" isn't about hearing, that is perfectly fine. In fact I think it is true the contrary, as people get older they usually lose hearing of higher frequencies, and so they might like brighter cans to hear some frequencies back. But now (I'm 36) we just are more "sensitive" to some frequencies, due to the shape of our ear canals or whatever. We don't hear them louder, they just hurt us.
Warm is a pair of cans where the bass is slightly elevated, they don't sound thin, but full and mellow. Treble can be a bit laid back. Then you can go full basshead, with a dark and cavernous sound (like my XB500, or some Beats), or go bright, with bass that doesn't impact that much but with elevated treble. X2 are supposed to be "natural", with slightly elevated bass. Sony 1A are supposedly darker, but not too much. These Sony mdr-100aap, as far these first description goes, sound like the X2, balanced with a little added bass. Perfect for anyone and for an all arounder sound. For us treble sensitive.. I don't know, I fear they might hurt. I hope to be able to try them in a store soon, albeit briefly.