Here is a really great explanation of how these little amps work:
This guy is more concerned with the visual aesthetics of the caps than the actual function. He never even checked the Sangamos, or the bias resistor. While the amp certainly works, is it really 'vintage tone' or 'worn-out tone'?
Danelectro is my favorite type of guitar, simply for the genius of their unorthodox, inexpensive, yet highly effective designs. I love the tone of old-growth masonite. If you are looking for details, the Pro-1 Bass is the most complete build documentation.
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Active electronics can add a lot of fun to a project, as well as save you a lot of soldering. Options range from simple buffers and pre-amps to tone controls to on-board effects.
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