AIMO you aren't really going to get any benefit from amping those headphones. I had both the 555s and the Tripples along with amps and I didn't find them to be very much beneficial; definitely not worth the price I paid for the improvement in sound. I was amping with a LOD from various iPods.
My experiance is much different, using my UM3X's, i find the SQ is noticably better when using my miny3. And it is not subtle. The separation and airyness is much better, sound stage seems to open up, and the low end goes from good to very, very good. The highs also seem to extend further and are much more pronounced, or at least separated from the mids better. As good as the HP out is, the amp makes it better. Now my CMoy, that is another story, it does little to no good, in fact i think it hurts the SQ, but keep in mind i am still playing with opamps, so there may be hope for it.
Again i kind of feel like i am hyjacking, cause im listening to a 4G iphone, but this post was more to state that i feel there is good reason to use an amp, even with sensitive IEMs. And i have a feeling that the new touch probably has a similar, if not identicle, chipset as the phone.
Just spent several hours listening through said rig while flying/driving to a jobsite out of state, and man it does sound good to these ears, i still am of the impression that it (with amp) is at least as good as the X. But many more hours will need to be spent compairing before i can say witch i prefer, if any. I do find that the X does not seem to improve as much with an amp, at least i dont notice that much of a change. Im pretty sure this is mainly due to the fact that sony uses a much more purpose built/powerfull chipset, this is with IEMs of course. For full sizex cans the amp helps quite a bit.
