With due respect to the members of this Forum, you'd be far better off at a specialty site like Head-Fi Head-Fi
A head amp is much like a power amp.....it needs to be matched to the headphones you are using.
Because of the low power requirements generally......there are a preponderance of valve head amps available but if you're using electrostatic head-phones or some planar-magnetics.....you may need more power than the 2-3 watts commonly available?
You'll find all the information you need on these sites.
Good luck.
A head amp is much like a power amp.....it needs to be matched to the headphones you are using.
Because of the low power requirements generally......there are a preponderance of valve head amps available but if you're using electrostatic head-phones or some planar-magnetics.....you may need more power than the 2-3 watts commonly available?
You'll find all the information you need on these sites.
Good luck.