OTL Tube Amps-- are they superior to everything?

I agree that a Berning ZOTL differs from a normal OTL amp. The ZOTL has all the advantages, and none of the limitations of "normal" OTL.

As many of you already know, I feel that the ZOTL is the premier audio design in history, thus far. That being said, if I heard a better sounding amp that I could afford, I'd buy it tomorrow. Don't think that's too likely, and not because I didn't have the money.

Agree that there are speaker limitations with just about any amplifier, even high power SS ones. Nothing matches with everything perfectly.

To answer your question directly, I feel that tube amps do music better than SS, and OTL gives a clearer faster insight into the music, with the right speakers. ZOTL does that even better, and can do some things a nomal OTL could never do, such as allow true SET configuration, without the use or limitation of traditional audio output transformers.

This is all my humble opinion, and is not meant to disparage any other type of amp, or its manufacturer, or owner. I use the ZOTL product, and know its capabilities.

Tubegroover, according to David's discussions, the ZOTL circuit is a transformer emulator circuit. It provides the impedance matching without the turns-ratio limitations and saturation limitations of traditional output transfomers. The circuit emulates the "perfect transformer" and doesn't suffer from the sonic limitations of these transformers. Therefore, the audio signal is not subjected to the performance limiting factors associated with output transformers. But the impedance matching is done in a much more efficient way than is possible with a transformer, without degrading signal integrity. This allows virtually vertical rise times in square wave response well beyond the audio range, and this is exhibited by the incredible speed of this amplifier. No audio output transformer can deliver this type of performance.

As far as comparing the ZOTL method to traditional OTL methods of impedance matching, the traditional OTL circuits use multiple sets of tubes in parallel to reduce the output impedance of the amp to a level which could be practical for driving a speaker. Due to the fact that they don't get the output impedance very low, they do better into higher impedance speaker loads. The ZOTL circuit gets the output impedance down to 1.8 ohms, and provides better damping factor into normal speaker impedances. And it does so with fewer tubes in the signal path.

To take this one step further, the Single-Ended ZOTL amps have only 2 tubes per channel(1 driver and 1 output triode). No traditional OTL can do that. The coherency provided by using one output triode in OTL, instead of a multiplicity of output tubes, is something that has never been heard, outside of the Berning circuit amps. So this goes beyond just impedance matching. There has never been a true single-ended triode OTL before this. That, in itself, is a major breakthrough, and is worthy of accolades for allowing closer insight into the music.

Yes, Allan, I studied this quite a bit before getting into Berning's amps. I also know about the RF carrier, and the "bus stop" get-on, and get-off routine. But I felt it was of no use to get into that here, because nobody has understood it previously, and I doubt anybody is going to get it now.

By the way, you should hear this battery powered, choke loaded 45 SE ZOTL. It's the cat's ass. I really would like to get an ear on those direct drive 270 amps you have too. I forgot what speakers you are matching them to. What are they?

Saxo, you have alot to learn. Is the poundage of heat sinks or the glitziness of a face plate the measure of an amplifier, in your opinion?

Do you buy your amps by the pound?

FYI, Berning has about the best reliability reputation over the last 25 years, of any manufacturer there is. The stuff never breaks. So much for the "stingy 2 year warranty" that you'll never need.

As far as being built in his garage, no, it's hand assembled by him. He actually builds each one of these himself, and you get an amp that is hand made by the most talented audio designer, probably in history.

Apparently, not only does he feel he should be paid well for his designs, so do the many customers who are WAITING IN LINE to get these amps. And when they do come up on the used market, they sell for about 85% of the new price, and are snapped up in the first few hours on the classified. Quite different than the 200 pound amps you seem to desire, which bring 40-50% of new, on the used market, and languish for days or weeks on the ad boards.

But the biggest thing you will miss is the sound that will destroy anything else you listen to in this price range. Perhaps you should look in the archives, where the Berning amps are repeatedly compared to amps costing $20k.

Don't get me wrong, you are entitled to your opinion about these amps. It was just so glaringly apparent that your opinion is poorly founded, that I had to make a comment.If you have a pre-concieved notion that you don't like OTLs, that's fine, but don't complain about the lack of weight when the whole purpose of OTL design is based on eliminating the heaviest part of a tube amp, which are the output transformers. Your comments show gross ignorance.

The Berning amp uses a high-speed switching supply instead of a normal power transformer. This was discovered to be superior about 20 years ago. So much for that argument.

You don't have to like the amp. But judge it on its merits, and not its weight. Weight has nothing to do with anything. As far as being ugly, ugly is as ugly does.

Sorry I came down so hard on you Saxo.