I have just purchased the latest Sound Lab M1

Dennis, you are the only person I've heard of saying Atma-Sphere MA-2s not being adequate to drive Sound Labs. There are quite a few happy owners out there using that combination, and for that matter MA-1s with the power supply boost option. You didn't say whether your M-1s did not have the backplate impedance update which is particularly useful when driving the speakers with OTL amplifiers. Additionally, did your speakers have the higher efficiency panels and (gray) high voltage bias power supplies?

Disclaimer: Sound Lab and Atma-Sphere dealer.

Hey Allan, let's not be condescending toward one another. I see this thread going nowhere (and far off topic, by the way) due to differences in perception and arguing semantics. A transformer is a transformer; you contend there are none, at least in the audio frequency band. It's not a matter of understanding, it's a matter of definition.

In the end the only thing that counts is the sound. I hope Winston, the originator of this discussion thread, is able to pursue some of the amplifiers suggested and recommend that he contact the respective retailers to audition the candidates in his system to make an informed purchasing decision.