I've been on a bit of a tear with PCB design lately. This one is a result of playing around with the El Sol/Acapulco schematic. I found something reasonably funny while looking through LM386 datasheets, namely that the Acapulco Gold - famed pedal "based on the sound of a cranked Sunn Model T" - is actually just two of the example circuits from the LM386 datasheet back-to-back with an RC filter between them and a voltage divider at the output. The marketing department's fun little story about an obscure tube amp that 99% of guitarists (including me) couldn't recognise in a blind sound test is a stroke of genius.
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Anyway, I wanted to add a gain control to give texture options, so I put a pot in series with the 10UF cap in the first LM386's gain loop. This means I can move between a lower gain all the way up to the stock Acapulco gain of 200. I added bypass caps for the biasing section of each LM386 as this can help with power supply noise. I also added in a James tone stack and will fine-tune the values once I do a test build. Lastly I gave the second amplification stage a slightly higher output to offset the insertion loss from the tone stack and any less-than-full-bore gain settings from the first amplification stage. Should still be a loud, aggressive pedal, but one with more tonal options than the original.