So after making the preamp and hooking it in the return jack of my 50watt guitar amp. I am really pleased with the overdrive sound of this preamp. I've enjoyed playing it the whole day. But i hear some problems that i cannot solved and needing some advise from this womderful forum.
So this is the thing.
The clean sound is somehow dull or lifeless unless i put a bright cap on the master volume. As i read in this forum, a 47p or 68p is the advised cap to put in. So works wonder. The clean sound is now have the clean highs which make my clean channel very pleasing yo play. But when i switch in to the overdrive. The highs are too harsh. It doesn't sound good. It sounds like a tearing paper to my ears. But when i remove the bright cap in the master volume. It makes the overdrive sound a lot better.
So i came up to this solution.
I tried to hook diffent cap values from 470pF, 680pF, 1nF, 22nF, 4.7nF and something in between to the 220k od entrance before the trim pot. I hook it as a low pass filter. So it goes like 220k - 1n to ground - 100k trimpot set to 26k. But it doesnt sound as good as the one without the bright cap.
Are there any options or suggestion you have that can help me in this matter? Thank you.


