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

I can't deny Ecclectique's assertion given his long experience directly with the question at hand but I have invariably lusted for more power. It is probably a silly leftover instinct when I was first buying good gear and a big amp had 60wpc. I have found with time and experience that it is the overall quality of the amp that ends up revealing greater dynamics and inner detail etc.
It is your money but my own choice of amps is quite conservative powerwise. I use mainly two tube amps a 60 watt integrated and 78 watt monoblocs. The speakers BTW in a big room are 92Db but absolute min impedance is low at 3.6 Ohm despite the nominal 8 Ohm rating. Tannoys do not drop thier impedance like my Focals do. Thus you're safe either way. FWIW I have heard both the 60 watt Atma (on special Coincidents) and the 100+ watt Atma many times and did prefer the bigger one (on Avalons). I have never heard the next one up you are considering.

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!
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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.