I think you maybe missing the boat going solid state on the m2's. Do you know if they have the impedance mods and diffusion ring?
If you can you should try a tube amp at least to see what these speakers can really do; The wolcott mentioned earlier is excellant advice; also higher powered vtl, manley,cary and my opinion the best match atma-sphere's ma1 or ma2 otl tube amps.
Also may want to try paul speltz's autoformers to help with the impedance curve these speakers have.
If you can you should try a tube amp at least to see what these speakers can really do; The wolcott mentioned earlier is excellant advice; also higher powered vtl, manley,cary and my opinion the best match atma-sphere's ma1 or ma2 otl tube amps.
Also may want to try paul speltz's autoformers to help with the impedance curve these speakers have.