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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This bass is a 21" scale, with a piezo saddle mounted in an adjustable bridge. The soundhole is just for looks. The strings are metal-wound Kalas. The fretboard is cut out of the ugliest piece of wood I ever received. For such a small neck, I managed to cut around most of the ugly, and the result isn't half bad.
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