Atma-Sphere MA-1 Mk.3.1 Vs. Atma-Sph. MA-2 Mk.3.1

Atma-Sphere amps are wonderful and the MA-1 and MA-2 are remarkably capable of driving a broad range of speakers. The key in matching an Atma-Sphere amp to a speaker is to think about the speaker impedance curve and phase shift. To drive speakers lower minimum impedances, choose an Atma-Sphere amp with more tubes. The greater number of tubes increases the ability of the amp to deal with low impedance speakers.

The big difference between the MA-1 and the MA-2 is, surprisingly, not a matter of power output, it's a matter of being able to drive a lower impedance speaker. Sure the power output is different, but the greater number of tubes in the MA-2 allows it to drive pretty much ANY speaker whereas the MA-1 will be happier with somewhat higher and more benign impedance curves.

I use MA-2 amps to drive my Avalon Eidolon speakers that have a nominal 4 ohm impedance, but do not drop below 3.6 ohms and otherwise have a fairly smooth impedance curve. The MA-1 will just not be as comfortable with that 3.6 ohm minimum impedance.

If your Tannoys have a nominal impedance of 8 ohms or greater, and if the minimum impedance doesn't drop below 6 ohms, the M-60 will probably match well. If the nominal or minimum impedance is lower, then look to the MA-1 or MA-2, with the MA-2 being the better choice the lower/steeper the impedance curve.

Your best resource will be to call Ralph and ask him about your specific speakers. He's likely to know other A-S amp owners with your speakers and he will give you good advice you can trust.

Atma-Sphere amps are superb, and I applaud your decision to focus on finding the right Atma-Sphere amps to work in your system. Good luck!
.

Mechans. With all due respect: re powering the Avalons with Atmasphere amps.
No doubt in my mind the MA-1 would be the better choice over the MA-60. The MA-60 hasn't a chance comparatively speaking here.
For that matter, even the MA-1's would be considered marginal at best when driving the Avalon. The only Atmasphere amplifier capable of getting the best from Avalons are the MA-2's.
For the record, my MA-2 mk2's were sold to an Avalon owner.
To be candid here: Even though your Focals are quite sensitive at 92 db, I wouldn't even consider Atmasphere amplification due to their lowish impedance load on the amplifier. Most all OTL topologies are not comfortable with impedances much under 6 ohms. As the impedance of the speaker drops, so does the wattage of the amplifier.

The Tannoy DC's impedance is very benign, nominally 8 ohms, typically around 9 ohms and never dips below 6.6 ohms. The perfect load for a Atma-sphere amplification.
In Donfibres room... Even with an extra 15db of headroom for the dynamic range over and above the power required I sincerely doubt more than 25 watts would ever be tapped.

Rushton. A great analogy and well said.

I was mistaken when I said the MA-1 was what I had heard several times. It was in fact Rushtons Avalons that were being driven by the MA-2. Forgive me for my error.
The speakers that the M-60s were driving have a very benign impedance they were Coincidents which I recall being rated at worst 11 Ohms. In any event I did acknowledge that the Tannoys were not known for dropping their impedance. Thus it was clearly up to the OP whether he would need the extra power.
I still stand by my remark however that the MA-2 on the Avalons sounded better but quite different than the M-60 on the Coincidents which have their own outstanding attributes. My amps have 4 Ohm taps so maybe that is why they can tolerate the more demanding load but they are paralell PP, not OTLs.

While I have never heard the 11 ohm Coincidents, I would imagine they would make for a very good match with any model Atma regardless of power.