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.
More: Danelectro Projects ...
This is an Evets '90s-vintage original reissue, made in Korea. These reissues are actually much better instruments than the originals from the 1960s. While a copper-burst would be more authentic, I like the sky blue better. The newer reissues are even more true to the originals.
More: Danelectro Longhorn Bass ...