Why no threads on OTL amps?

A little surprised not to have noticed Atma-Spheres on this thread. Compared to the other amps I have owned, tube or solid-state, the MA-2's have outperformed all in nearly every category. Bottom slam, midrange transparency, and extension up top...all beautiful and musical. This, of course, is with the system I have assembled. Avalon Eidelon, Jadis preamp, CEC/ Audio Note digital, Clearaudio TT, FIM cable. I have enjoyed many systems, but none for as long or as consistently as that which I have forementioned.

Reliability has so far been a non-issue. The 220 watts/ channel offers more than enough juice. The heat generated is something else. My room must increase a good 8-10 degrees. Great in winter, but summer....

I have not compared to other OTL's but reports on performance carries similar subjective remarks. A cleansing in clarity, bringing the listening experience closer to the recording venue. Must be heard in a well designed system.

Let me join Siddh in praise of Atma-Sphere OTL's, neglected in most of this thread. I'm using a pair of M60 II.2's with half their output tubes removed, with Quad ESL 63's, whose impedance drops as low as 4 ohms though is mostly closer to 7. The point being, that's high enough. Not the 16 ohms some OTL's may need. Reliability is fine too. I did an odd experiment, using a Pass Aleph 3 as a monoblock (input and output both paralleled) for one speaker and a M60 II.2 for the other. There was nothing clearly wrong with the Aleph 3 sound, as I switched back and forth on good mono material, but I preferred the warmth of the M60 II.2 sound every time. I wasn't giving up anything, detail, transparency, certainly not palpability if we may speak of that, as far as I could tell. That made me decide I was a tube person for life.

The Berning ZH-270 is just a marvelous amplifier that can drive many speakers with ease. This amp is very musical, quiet, and has lots of drive! The ZH-270 is revolutionary and best described by Thorty40 and Kenl. I love my ZH-270 and would only consider replacing my present system with a Seigfried or Art Audio amp with a high efficiency horn speaker.

C'mon, where are the Graaf and Croft people? And how about the Transcendance folks?

Twl I am also a Transcendent folk, still have it. A great little 25 watt amp it is. This is the one that brought me to the realization of what OTL amps are all about. I doubt that you can do better at the price and power rating.

Regardless of which of the OTL amps that are choosen for a given application and load the one indisputable fact is that these amps as a group are uniquely special. After all, this isn't a p...ing contest, is it? I have not had the priviledge of hearing the Joules, Graff or Tenor but I'm sure they have their virtues and that each might be picked over the other in a given application.

My problem with Siddh's choice is that I can't live in Florida with an increase of 8-10 degrees in my room, the plants would wilt and so would I. I'm sure I could live with its sonics which by all accounts is among the best. But 220 OTL watts, must put out 1200-1500 watts at idle. I guess I could settle for the M-60's, still a lot of heat. This is why I went with the Transcendent originally but ultimately it didn't have quite enough headroom with certain music.

The Atmaspheres, Joules and Tenors may be better on an absolute level than the Berning with a given speaker system. The Berning would be a better choice for me with my speakers and probably would be a better all around choice for a lot more audiophiles. What other tube amp increases power ala ss into low impedance loads? Transformers saturate and compromise the bass and high frequency performance and OTL's start doing crazy things to the dynamics of the music and become unstable into such loads. Well you just add more tubes to up the current. Sounds like a great choice if you live in a cool climate or have a dedicated venting system for the amps. This is the whole point of Bernings' design.