OMG people, I can't believe my eyes... the LARGEST audiophile forum in the WORLD, and no single meaningful answer for 3 months.
MH01, you will be happier with me
I digged quite a heap of forums and here is the short list of the best(?) portable amps for AK120 / AK100:
CEntrance HiFi-M8 (LX configuration) - probably, the best choice at the moment.
Ray Samuels RSA-SR71B - also very cool amp with powerful output.
ALO audio Rx Mk3-B+ - also very frequent choice.
Ray Samuels Intruder - know little about it, but also recommended option.
Bispa PHPA 05B - they say AK120 sounds better than other top-grade players with it... (means Colorfly C4, HiFiMANs obviously)
FiiO E17 - cheap and questionable option for AK120 (but very good amp aside of A&K). You should listen to know the difference between this and 2-4 times more expensive amps (listed above).
I haven't heard any of these amps, but want to buy an amp in foreseeable future.
I highly recommend to listen first(c) before bying, if you have on opportunity.
Also, you should read recommendations from this thread:
why you need an amp for ak120, or.. why you need ak120 for getting an amp.. kind of wasting
Edited by VladGuardian - 1/11/14 at 5:26am