[Kyle98750]

I want to power the Beyerdynamic DT-990 Pro.
Will a Fiio E10 Work or a Fiio D3 paired with a Behringer HA400?
Which will sound better?

 

[swifty7]

whatever you do avoid purchasing the ha-400.  It will devoid the life out of your headphones.  It turned my ath-ad900x into $20 headphones.  It's cheap for a reason.