On Jan 24, 10:24*am, "Stephen Cowell"
wrote:
"Morris Slutsky" wrote
...
I don't know if it's original or not, in the context of a guitar amp,
but I think it's pretty neat.
http://img718.imageshack.us/img718/8...edfeedback.png
I like it! *Two thoughts:
1.) *If you replace one gain stage with this, you'll
* * invert the signal... this can cause problems sometimes.
2.) *Switching the cathode cap out also rolls off lows.
I'd like to hear it in action.
__
Steve
.
Looks good! More thoughts... (for a flat frequency response
application)
-- use a much larger cap than 0.44 uF, e.g. 100 uF, for cathode
decouplng (and feedback) over a much wider frequency range
-- plate load on the 2nd triode is 100K//47K (at least when switch is
closed), or about 32K; this seems a bit low.
-- bypass the 2nd triode cathode resistor (and make it smaller, e,g.
2.7K) for more gain, then increase the above 47K for the right amount
of feedback
This design might serve to switch a single audio input from microphone
gain to AUX gain (not tried)
Cheers,
Roger