Why no threads on OTL amps?

Very good points from all.

However, there are dozens of ZH-270 owners that have had trouble free operation for over 5 years.
With an expected output tube life of 20 years, it's safe to say that one can also expect the same in trouble free years from this unit.

I don't know whether I should post this or not, but here goes....

I read some comments by David Berning himself once about whether his amp is an OTL. I know, I should have the web address for this, but I can't find it right now. I will look for it. It was either on an old thread (2 years ago?) on Audio Asylum, or on a webpage by Gizmo Rosenberg (not sure of spelling). If I remember right, Berning preferred the term ZH (zero hysterisis) over OTL because of issues like those that have arisen here. I have seen Berning amps referred to as ZOTL's. Again, if I remember right, that phrase was coined by Rosenberg. Now, this was a while ago that I read this, so my memory may be faulty (gets worse every year, sometimes every day I think). When I find the address, I'll post it if anyone's interested. But really, like I said before, call it what you will--the issue is PERFORMANCE. When I get my tax refund, I'm planning on buying a used Joule Electra and having a shootout.

John

those comments were in Positive Feedback in the letter's section a few years back.....he and Gizmo were going at it good as i recall.....i have the issue....will dig it out later.

You could try effeciency speakers like Lowther ,AER or Voxativ with 16 ohms impedance,I am using a pair Goodmans 612 fullrange speaker 16 ohms with very good results.