[l2aven]

Well, now I own Beats - Studio (I got it for 200US still expensive though). I know a lot of people here don't like beats but I have already owned it for a year. 
Back to the topic, I wanna know whether Beats Studio ,which already has integrated amp inside is capable for using with amp/DAC? I am making a decision to choose NuForce mobile, Fiio E7, or Hifiman EF2A. Could you guys please give me some advices?

 

[kboe]

 
 
I don't think the Beats would improve with an amp as the people who designed them never intended them to be used in conjunction with one.  That said however, you may be pleasantly surprised.  Every, EVERY headphone I've ever owned has improved with the aid of good amplification, even ones meant to be run straight off an iPod or mp3 player.  If you buy the amp and don't get any better results, you can always keep it for the next headphone.