With the application of electricity, guitars went from gentle acoustic vibrations to a magnitude 10 earthquake. Tube guitar amplifiers are the classic design, first created (along with the first magnetic pickups) in the 1920s for jazz players so they could be heard over large ensembles. The amps have a rich tone with a pleasing creaminess when distorted. The “vacuum” part of the tubes is important because the absence of air allows electrons to travel through the wires and components. Although this tangle of innards may look like a rat’s nest, it’s actually a logical path from string to speaker. Those entrails channel electricity propelled by vacuum tubes from the pickups to the preamplifier to the power amplifier to the output transformer (which feeds the speaker) and back again. The interaction of pre- and power amps creates wattage and volume. Spinal Tap fans should also take note that some Fender amplifiers from the 50s actually go up to 12.