I am looking for suggestions for master volume for my 50W Marshall clone. I guess there isn't right or wrong approach because every different implementation yields different sound-tone, whatever someone likes. I have seen 3 different schematics. Also found some info here....but not real answers.
Ken Fisher type I/II and LarMar. PPIMV
I like the "B" version as seen on the link I posted. The question is what happens with frequencies when volume is all the way up and those two caps are connected in series. My coupling caps coming from the 3rd pramp stage from invertor are 0.022uF, grid stoppers are 5k6. I have to also mention that bias voltage goes as high (or low,... depends how you look at it) to -4VDC. I would like to keep the sound as is without any frequency roll off or alteration. Something like the pot is not there at all. I tried another version with the master volume before the PI as the original Marshall JCM800 has, but it doesn't work well with power scaling. It is difficult to keep the amp in overdrive in low volumes because the master volume before the "PI" also affects the overdrive. Any suggestions?
Ken Fisher type I/II and LarMar. PPIMV
I like the "B" version as seen on the link I posted. The question is what happens with frequencies when volume is all the way up and those two caps are connected in series. My coupling caps coming from the 3rd pramp stage from invertor are 0.022uF, grid stoppers are 5k6. I have to also mention that bias voltage goes as high (or low,... depends how you look at it) to -4VDC. I would like to keep the sound as is without any frequency roll off or alteration. Something like the pot is not there at all. I tried another version with the master volume before the PI as the original Marshall JCM800 has, but it doesn't work well with power scaling. It is difficult to keep the amp in overdrive in low volumes because the master volume before the "PI" also affects the overdrive. Any suggestions?
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Nothing.
The new .2 caps are WAY larger than original .022 so you won´t hear them.
REALLY?
If so your tubes would redplate and melt.
You *are* using all coupling caps I believe.
As shown on B) , no sound change.
Build the B version.
Somehow you forgot to mention that "small" detail.
My mother used to do that. Tells me a recipe and it does not turn out. When asked about adding 'XX' ingredient, "Well of course you would put 'XX' in!"
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