Recommended Speaker List for Atma-Sphere OTL Amplifiers.

I use M60s and an MP-3 in my system first with Audiokinesis Jazz Modules and now Quad ESL 57s. I’m getting a pair of Spendor 1/2E speakers to use with them as well.

Dealer disclaimer.

I have had a number of people listen to my Jazz Modules. One in particular who is pretty well known in the audio world mentioned that they sounded better than the German and other exotic horns he has heard. If you do visit Duke and hear his speakers I'm pretty sure you'll drop that exotic requirement. I only sold my Jazz Modules because my bi-amped ESL 57 set up with multiple woofers in a "swarm" array (ala Duke) gave me the benefit of what the ESL 57 does best without the bass limitations and resonance issues of those speakers.

In the M60s the single driver tube in the front is critical as this tube affects the DC offset function. If you ever have issues setting the DC offset, that tube should be the primary suspect. I ordered Russian tubes from Ralph a while back and just by chance won an eBay auction for another set (seller happened to be Andy at VTS). Per Ralph, the key to the power tubes is to condition them for 96 hours before applying the B+. So just let them sit in the amp with the filament switch on for 4 days.