atma sphere ma60mkii and revel studios

The speakers are 87dB sensitive. With an autoformer the 3 ohm impedance issue would effectively be nulled. You still have a 60 watt amp driving 87db speakers.

Not enough.

As someone who tried the Zero Autoformers with my AtmaSphere M60s, they are not a very good option, in my experience.

Yes, they allow the OTL amps to see a higher impedance. Yes, the allow the amps to drive a speaker they would not normally mate well with. No, they do not make good sound. The MAGIC of the Atmas are that there is life and soul to the music, combining the best of what solid state(speed, clarity, frequency extension) and tubes(reality, presence, beauty) and remove the tube part of the equation.

We found the sound in my system and my friends to be bleached out and very white sounding, in addition to having a tendency to become overdamped. At that point, why wouldn't you just use a solid state amp?

I think the ZEROs are very much case dependant. I had fabulous results with mine on a previous set of speakers. The speakers used were N.E.A.R. 50Me II's with a nominal rating of 8 ohms. They are rated at 87dB and the M-60's drove them exquisitely in a large room.

My current speakers have a higher impedance and are better served by using XLO Signature Shotgun cables.

Hey, Trelja!

Don't you know those damn tube amps are just distortion machines and can't be trusted?!? You'd be better off getting a good spec'd Technics receiver with .0000000025% THD and a built in graphic equalizer.

You are oh so right, Tom! If it measures better, it must be better.

Wellfed, I agree that the Zeroes allow one to use the Atmas, just feel that they seriously hurt the sound in the various cases me and a friend have tried them in. A buddy here loaned both of us a pair to play around with for a month. My friend's comment was that he wanted to try them as he felt very strongly a transformer was needed somehere in the audio chain. After playing around with two different pairs of speakers, I felt like I must have been a misfit, because these things destroyed what the Atmas were best at. Sheepishly telling him my experience after a few weeks, he immediately agreed, saying he came to the same conclusion. When we both let our lender friend know this, even he did not disagree.

My suggestions for someone interested in AtmaSphere: There are enough good speakers that mate well with the M60s to choose from, and if you insist on having one that doesn't, move up to a bigger AtmaSphere amplifier.