Headphones at work


I have a set of HD650's I would like to use at work with my pc and / or MP3. Other than plugging them into the sources, what equipment would I use to realize their full potentail. I have read USB amps may not add much. I could use your advice and consultation.

Thank you in advance.
bgmyers
Good point, Swamp. Another good argument for IEM's which are the best at isolating.
I use a pair of 650's which sound great with either my desktop or my laptop using a couple of Headroom's portable components:
The MicroDAC http://www.headroomelectronics.com/products/micro-line/the-headroom-micro-dac/
. . . and the Headroom Cosmic Headphone Amplifier http://www.enjoythemusic.com/magazine/equipment/0402/headroomsennheiser.htm
These are earlier models, this is the current package:
http://www.headphone.com/packages/headroom-micro-amp--micro-dac-package.php
Sort of expensive, but if you already have the 650's, worth it. And besides, just because you're 'at work', you may still be alone with no one to disturb ;--) I'd take the Sennies over in ear's anytime.
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