[everybest]

In terms of  buying new equipment for my headphones I am fairly new to this.
 
I have a AKG K702 that sounds mediocre out directly out of the PC.  The sound is coming directly from an Asus P8Z77-V Deluxe motherboard.  
 
I have a roughly $200-400 budget, would the O2+ODAC be a good choice? (http://www.jdslabs.com/item.php?fetchitem=48)
 
Do I need a dedicated soundcard or would it make a significant difference?

 

[KT66]

Have a look at something like the Audioengine D1, easy to use, sounds superb 
and can integrate with your main hifi.
 
Play lossless files using Foobar or something similar that lets you bypass the soundcard entirely.

 

[everybest]

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