I use one of the Sonic T-amps (the cheap one, not one of the newer "fancy" ones) in my wife's office with a pair of M3s and they sound great. I bought an external power supply for it, and the clips are a little cheesey (& difficult to get decent speaker wire into). So it might be worth spending a little extra to get the full fledged "audiophile" version.

I'm not going to say this amp is the finest product in audiophiledom, etc. but it is a fine value and does the job effectively. And you can certainly find it for less than the link to Sonic Impact that I included above. There are prior threads about the cheap version in the archives.

Good luck!

Regards,
Rich