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Robert Baer

Maynard A. Philbrook Jr. wrote:
In ,
says...

Jim Thompson wrote:
On Mon, 02 Dec 2013 12:58:56 -0600, Tim Wescott
wrote:

It's winter, and the amplifier in my PC speakers just died.

I think it'd be kinda cool to have a toob speaker amp, but I'm too lazy
(and time-challenged) to build one up from scratch.

Are there, by any chance, kits out there? I'm not looking for nickel-
cored transformers with solid silver windings, genuine paper caps rolled
on the thighs of virgins, toobs dipped in LN2, and all that crap: I'm
just looking for something that'll give the audio quality of a mid-range
amplified speaker set, in a cabinet that shows off the fact that it all
uses ancient technology to get the job done.

Suggestions welcome.

TIA

Just for fun, you might do a single stage class-A stage using a 2A3. I
did one when I was a kid, but with 5 in parallel ;-)

...Jim Thompson
Better yet, a push-pull transformerless design!

I remember a quasie tube output, that was bad car ma.

It required a safety circuit on the output, not for users but for
equipment. The outfit could care less about the user safety!

This was a magnetic server that required a broad range of bw.
the tube outputs were a pair of 4-400Z. Had dual HV supply because you
needed the - rail for the bottom side. each heater had their own
transformer with CT to tie off to the common for pinch off biasing.

The top side had some strange method of driving the tube, but it worked

Jamie

I may still have circuits and/or designs of transformerless tube
speaker drivers that were purported to be perfectly safe to touch active
lines (do not ask which lines, do not remember).
And yes, the circuitry is weird on the push-pull drivers; there was
even a full bridge version.