Which headphones??

For soundstage and imaging, you may be better off with open backed headphones. Soundstaging and imaging are precisely what you tend to lose on a closed headphone.

Around $200-300, you might want to try the modded Fostex headphones by Mad Dog. They get excellent reviews, and are closed backed.

Senn Headphones tend to have a pretty relaxed sound in my experiences, and they are also among the most comfortable brands I have tried.

As for higher-end headphones, I'd recommend taking advantage of The Cable Company's lending library. I think that this service is only for headphones above a certain price point. But at these higher price points, you are getting some pretty spectacular sound. Though you will be limited by the zDAC on some of these higher end headphones. I am a huge fan of the HiFiMan HE-5LEs that I have, and other headphones in their line are also excellent (though I'd stick to their orthos).

As with most things audio: audition, audition, audition.

B_limo,

Have you contacted The Cable Company to see if the 600s or 650s (or similarly priced models from HiFiMan, Grado, Beyerdynamic, Denon etc.) are available from their lending library?

Find a way to listen to at least a few different cans before pulling the trigger. And hear for yourself the difference between open and closed cans.

Well, if you are going with the ZDDac, then I'd avoid the harder to drive HiFiMan cans.

But I am not sure where the problem is.

If the Cable Company carries headphones in the price range you are looking at in their Lending Library, I'd take advantage of that. Headphones are light and cheap to ship, so I'd find a way to try some out if you can find a way.

Audition, Audition, Audition. You can use HeadFi etc to narrow down the choices. A'gon forums are great for a lot of things, but HeadFi is the king of headphone forums. Some Looong threads tho.