Quote:
Originally Posted by
glunteer 
In my PC, I have Asus Xonar DX
The Xonar DX is a good sound, just not that great for driving headphones, guess that's why you want a headphone amplifier.
The JVC HA-S500 does not need much in the way of amping, but works better with an amplifier with a low impedance (Ohm) output
Impedance is resistance, measured in Ohms.
(The output line-out/headphone jack on the Xonar DX is very high Ohm).
The Fiio E11 portable headphone amplifier comes with a very low impedance, like .5-Ohms (NICE).
Get the Fiio E11 with an extra battery and a simple AC powered battery recharger.
You can be recharging the spare battery while the Fiio E11 uses the other battery.
The Fiio E11 can drive Beyerdynamic 250-Ohm headphones.