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previous: BrianH Does anyone know how Kevin O'Conner... -- 10/18/2000 8:04 PM

Re: How does "Power Scaling" work?

10/19/2000 11:16 AM
Stephen Conner	Re: How does "Power Scaling" work? There was a lot of talk about power scaling on here earlier this year. Basically it uses an 'AC linear regulator' which is just an electronic variac controlled by the power scaling knob. That feeds the PT primary, so allows you to adjust the B+. The bias supply varies in proportion too, which is just what you want. A separate transformer is used for the heaters (and maybe the preamp B+ too) You might get schematics in one of O'Connor's The Ultimate Tone books. There are other ways of doing power scaling though. You just need to drop the B+, and the bias supply proportionately. I designed an amp with a high-voltage B+ regulator a while back. Although I never did, it could easily be modded for power scaling. I'll try it out in my next amp. http://homepages.strath.ac.uk/~cnbp111/toaster.html Steve C.

10/19/2000 11:16 AM

Stephen Conner

Re: How does "Power Scaling" work?

There was a lot of talk about power scaling on here earlier this year. Basically it uses an 'AC linear regulator' which is just an electronic variac controlled by the power scaling knob. That feeds the PT primary, so allows you to adjust the B+. The bias supply varies in proportion too, which is just what you want.

A separate transformer is used for the heaters (and maybe the preamp B+ too)

You might get schematics in one of O'Connor's The Ultimate Tone books.

There are other ways of doing power scaling though. You just need to drop the B+, and the bias supply proportionately. I designed an amp with a high-voltage B+ regulator a while back. Although I never did, it could easily be modded for power scaling. I'll try it out in my next amp.

http://homepages.strath.ac.uk/~cnbp111/toaster.html

Steve C.

Replies:

Craig Re: How does "Power Scaling" work? -- 10/24/2000 1:46 AM