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In Reply to: Re: I do use OTL's and personally love them... posted by Lew on October 20, 2004 at 12:39:16:
The Futterman amps had no circuit board. Because of high negative feedback the input tube which provided all the voltage gain in the amp (6EJ7) had to be physically very close to the RCA type input socket. I found the best 6EJ7 tube for my H3AA's to be Siemens Halske made in Western Germany. These have mesh plates. Far superior to anything else I tried, and I tried every 6EJ7 type I could find.New York Audio Labs used circuit boards. Futterman did not. I think this was a critical factor in how each approach to essentially the same circuit sounded different. It was conveyed to me that this fact was particularly annoying to NYAL; that what Julius' built on a Budd box in his appartment just sounded better. He did not use fancy parts. I got the feeling he shopped for the best deal on what he needed at the time.
The H3AA had no power switch, just an attached power cord. I remember it was always interesting to plug them in. On cold start the current inrush was so huge it would dim the lights and the amplifier would almost physically jump. The transformer would emit a short groaning sound and settle down to a low almost inaudible hum. Never blew a fuse though. The amps worked every time. No failures, no smoke, and no fires. It was really something to see the forest of tubes perched on top all lit up.
Each 6LF6, the last of the line of increasingly more powerful horizontal output tubes made for color television, was individually fused with a small piece of #44 copper wire. If the tube shorted the wire would vaporize. Neat and inexpensive protection. I think it was the reality of ever more expensive and poorer quality 6LF6 which caused me to accept an offer to purchase.
The great magic with the H3AA happened with electrostatic speakers, though I got great results with dynamic types. It was the midrange that would make you sit down and listen. Grain free, musical, entrancing. It was truly magical.
The OTL works best into higher impedances, as we all know. I think if speakers were offered with 16 or 32 Ohm voice coils it would spark a renewed interest in OTL.
PS - a quick note re Ralph K and Atma-Sphere. It always sticks in my craw that talent/brains/creativity can be overcome by jealousy, greed, lust for power/control, or whatever. I have seen it many times in many companies ( and countries ). I hope Ralph can take some comfort in the fact that many many loyal customers and fans of his opus are standing behind him no matter what.
It should give those who have fomented this coup pause. Perhaps it would be unwise to treat Ralph unfairly. It could hurt the company, the product, and themselves. Better think about it, boys, unless you are just thinking of yourselves.
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Follow Ups
- Re: I do use OTL's and personally love them... - elektron 09:37:01 10/21/04 (4)
- Ditto on both Futterman and Karsten - Lew 12:35:58 10/21/04 (3)
- Re: Futterman and Karsten - Mike Mount 21:18:50 10/21/04 (2)
- Re: Futterman and Karsten - Lew 07:21:31 10/22/04 (1)
- Re: Futterman and Karsten - Mike Mount 21:12:13 10/22/04 (0)
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