[Dragnerok X]

Title covers most of it, but here are a few additional points:

• Closed-back is unfortunately non-negotiable, because I have a very loud air conditioner to contend with.
• A good soundstage would be nice, but I acknowledge this is difficult to achieve with closed-back headphones and am willing to settle for just well-defined imaging.
• I'm aiming for a sound signature that is as close to neutral as possible. For reference, I own a pair of m50s and am bothered by how subdued male vocals are vs the rest of the mix.
• I don't own an amp, but you can tack on another $150 to my budget if one is deemed necessary.

 

[serman005]

A B&W P7 or a Meze 99 Classics or a B&O H6 all come to mind. Maybe read about them and see what you think. It is possible one of these could work for you.