Congratulations Atmasphere!
I noticed today that Ralph Karsten (whom regular and even occasional participants in this forum will of course recognize as the designer and proprietor of Atma-Sphere Music Systems, as well as a uniquely valuable contributor to the forum) was granted United States patent number 10,469,042 on November 5, 2019. It covers an audio amplification technique he had indicated here that he has been developing, which in simple terms appears to me to basically be a clever combination of an analog-to-pulse train converter (as used in traditional class D amplifiers for example, among other audio-related applications), with an output stage employing circlotron topology (analogous to the topology used in his OTL power amplifiers, but utilizing solid state devices).
Congratulations Ralph!!
Best regards,
--Al
Al was both a gentleman and a scholar. Also a good engineer, in case scholarly pursuits and engineering aren't the same. I miss him as well. |
I could not be happier (perhaps ignorance is bliss) with my M-60s. I'd be at a loss to imagine how they could be improved upon with respect to sound. Not saying the M-60s are the worlds best sounding amps, just saying that my 3.3s with the current tube complement have not been bettered by anything I personally have heard at any price.This is all about the way the loudspeaker and amplifier work together. Some speakers don't like a lot of damping and then our OTLs play them nicely. Other loudspeakers simply can't be driven well by any tube amp without feedback; that's what the class D is for. In both cases the idea is to minimize higher ordered harmonic production and IMD to prevent harshness. Someday maybe there will be a 'universal amplifier' but IMO that's still a ways off. Thanks for all your comments :) Have a Happy Thanksgiving! |
So, If I understand what Al has written, Ralph has created a symmetrical bridged class D tube amplifier.... Of course, I’m guessing, but I’d love to hear more.@timlub The tube part isn’t right, but otherwise, yes. Essentially the invention is a Circlotron class D amplifier. Prior to this the prior art was either half-bridge or full-bridge; the former needing two output devices which are arranged in a ’totem-pole’ configuration (and is a fairly simple circuit), the latter being two half bridge circuits driven in opposition. Now there is a third means, the Circlotron, which has more in common with a half bridge circuit except for two important changes: its symmetrical and the output devices are not directly in series with each other. Its the latter bit that is the most interesting, as this essentially reduces shoot-through currents which allows for a circuit with less dead time. In a nutshell its a method of reducing distortion in a class D design. |
