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Bio: I'm 34 years old and work on MI amps and do some cattle ranching.
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I'm trying to figure out the best way to apply a SUS control to a cathode biased SE amp I'm building. Overall the topology will be similar to Blackface Champ but it will have Power Scaling and I'd like to add a SUS control. For the limit control I was planning on adding a Master Volume before the grid stopper of the power tube. Can the SUS circuit connect where the Master Volume pot usually grounds or is it better to have it work off a grid leak resistor after the master volume control? Thanks for the help!
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Hey
Note that the SUS effect is SUBTLE and may be swamped by what Power Scaling can do for you.
As a cathode-biased amp, SUS-2 can be applied around the output stage. It can also be applied to any preamp stage that might clip, however, in the case of the Champ topology only the second stage qualifies and just barely. The two 12AX7 stages can only make a mild overdrive at best, and that will produce way more drive than the 6V6 needs to produce full output. With the MV / Drive Compensation control directly ahead of the 6V6, the situation can be tamed.
Best to remove the feedback loop if present.
Have fun
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Hi makinrose
SUS is NOT a Boss compressor pedal effect and won't do what you are thinking for the clan sound.
Circuits like the Champ cry out for more gain, so adding a tube will open up millions of possibilities for much warmer clean sounds and far better distortion sounds, just as the Champ chapter of TUT3 illustrates in its 36-pages.
Have fun