OTL Tube Amp for Maggie 3.6?

I know that the Zeros are an autotransformer but isn't the big reason of the sound of otl's is because they do not have an output transformer. Now we stick one back into the equation. Seems conter intuitive

4est - I actually love the Aleph 5 on them. One thing I was thinking of doing is adding a Class D (because the xover point on the 3.6 is so low so the negatives don't come into play - 200 hz) and doing active crossover, and keeping the Aleph 5 for the high end. It sounds quite amazing an Jazz vocals and lots of stuff. The aleph 5 in a lot of ways is as close as you can get to the smoothness of a tube amp with solid-state, but still get higher watts at lower impedances, and the ease of a solid-state.

You are right, however, there are tradeoffs in everything. I have an old Luxman in my garage from the 80s with something like 800 watts at 4 ohms. It is a very different experience, and has plenty of PRAT. That is why I was thinking of adding a Class D device for the bass panel.

But in reading about certain electrostatics that are crazy big-buck, it seems that OTL tube has been considered the 'best' amp that exists (I know, I know...). Just expensive. So seeing what can be done, and as I'm a tinkerer I don't mind putting one together myself and seeing what happens, the Beast seems like an option.

Also, the idea behind using the Beast is that it might be powerful enough as a single amp to just stick with passive xover. I don't see a lot of high power OTL tube amps for reasonable amounts of money. I have a modded passive xover, and also I have a 3.6 late-model refresh xover that basically no one knows about, but anyhow it sounds great. So sticking with passive is fine.

My other options are:

XRV1 with Class D on low end (maybe even NuForce 8.5)

OTL Tube

Pass 60.5 or 350.5

magfan - OTL does something that can't otherwise be done. There is magic there. If you can hear them locally, find some Joule Electra dealer and prepare to be stunned... Also their pre-amps are no slouch :). But I'm trying to find a cheaper way to get the Joule Electra sound.

Atmasphere - I'm not against that at all, although per Ahendler's comment, I'd really like to do it without Zero's.

I guess another option is XVR1 or Bryston with lower power OTL on top end and NuForce 8.5 or other ClassD on lower end. Honestly I suspect that Rotel would be find given the xover point. That all can start getting pretty expensive, though. Bryston xover and Rotel ClassD would help make it affordable.

Atmasphere - would it be hard to have a MA-1 or MA-2 that is made for lower impedance loads? I see this comment on your website: "The MA-2 in particular is noted for its superior performance on Sound Lab, Wilson Audio, JM Labs, Magnaplanar and Avalon loudspeakers (90% of all MA-2s built are running on these speakers)" but still - not knowing electronic details, instead of a 4-ohm switch, maybe a 3-Ohm switch? I don't know if it would in the end make much of a difference, but it sounds like for OTL it might be an important difference. Of course you'd want to check the 3.7 these days and see if it is 3.25 Ohms like 3.6 (see next paragraph).

From 3 kHz to 50 kHz the impedance is around 3.25 Ohms. From 10 Hz to 1 kHz it is more around 5. There is some funny stuff inbetween, it peaks very high briefly.

Phase angle is 0 from 10 Hz to 1 kHz and linearly moves up from -22.5 to 40 between 2 kHz and 50 kHz. Stops at maybe 15 deg at 20 kHz?

If I went with Bryston xover and Rotel ClassD I could use the Aleph5 for another several years and then add an OTL for top end later. That actually could make a lot of sense.

And in terms of going from A to B I could even use the 800 watts in my garage in the short term, so that would just mean getting the Bryston xover for now...

But I really like the idea of OTL. I'm obviously not sure if OTL on top end and ClassD on low end may be too different of a sound, if speed is different, if somehow it would be too different and people could tell.

I mentioned so many things, just to say, lets keep this thread on the topic of OTL amps as applied to Maggie 3.6 or 3.7s (or 10s if there is experience with that out there).

03-25-11: Ahendler
I know that the Zeros are an autotransformer but isn't the big reason of the sound of otl's is because they do not have an output transformer. Now we stick one back into the equation. Seems counter intuitive.

Yes, it does seem counter-intuitive, but the FAQ on the Zero's has what seems to be good rationale:

What is the difference between the ZEROs autoformer and a typical tube amplifier's transformer?

The ZEROs have a few advantages over "typical" tube amp transformers:

A) The music comes out on the same winding wire that it goes in on so the music does not have to pass from a primary winding to a secondary winding.

B) There is no DC current to contend with. When a transformer is made to accommodate a DC field, its audio transparence is compromised.

C) The impedance ratio is very small (16 ohms to 4 ohms, compared to a few thousand ohms to 4 ohms). This simply means that it is much easier to achieve things like, frequency response extremes, than with a "typical" tube amp transformer. The ZEROs sport a frequence response of 2 Hz to 2 MHz.

Regards,
-- Al

The MA 3s looks good on power, but I'm trying to stay under 6 figures.