✪ CAUTION. The reverb circuits on this page aren't guitar stomp boxes! Don't try to adapt them for guitar. Guitar reverbs require a reverb tank driver on the input of the tank. (This tank driver is an amplifier with a high impedance front end.)

Spring reverb tanks began as organ effects, contributing cathedral ambience to home organs. For many years, Gibbs produced magnificent reverb spring tanks for Hammond organs. Gibbs was a Hammond subsidiary. Today, Gibbs' successor is Accutronics (Accu-Bell), itself a subsidiary of Belton.

Tight squeeze. An electronic organ had room for a 14-inch reverb tank. But a car certainly didn't! To appeal to guitar amplifier makers, Gibbs miniaturized its spring tank. What was good for the goose was good for the gander: The new, Type 5G guitar tank could squeeze under a car's rear deck. At last, concert hall ambience became available to commuters and travelers on the open road. And a new market presented itself to Gibbs.

Radio Shack's best reverb, still fits under dash: Kinematix^® with 3 controls: Volume & balance pots & on/off switch. Four transistors. Pos or neg gnd. '67 catalog, p. 116. ($34.95).

Car clutter. Still, a car reverb spelled clutter and complexity: An under-dashboard control unit, a rear speaker, plus a spring tank and amp in the trunk. In short, a “traffic jam” in the cockpit. Fortunately, by the early 1960s, germanium transistors replaced the ungainly vibrators and tubes of earlier reverb amplifiers: Slimmer size, reduced weight, lower power requirements, less heat. But that reverb tank: What to do? At the time, even a “short stack” tank was still over nine inches long: Too massive to fit under most dashboards!

But the reverb avant garde marched on. Gibbs led a reverb revolution in 1966. That year, Gibbs began to offer its miniature spring tank. This Type VII tank had two springs and was only three inches long: Perfect for the cramped interior of an automobile, even the tiny Rambler American. For the first time, a car reverb could nestle right inside the control unit, under the dash. And the miracle of solid-state electronics allowed a small amplifier to squeeze in the tiny reverb box, too! The under-dash revolution proved we were celebrating reverb's golden era.

Leak? Nevermore! By 1969, car reverb manufacturers had replaced leaky germanium transistors with stable, robust, more sensitive silicon parts. About the same time, stereo radios and tape players arrived. Reverbs adapted, adding their enchantment to the mobile world.

Craze. Reverbs with mini-tanks became a craze. For a few years in the '60s and '70s, you couldn't open a car catalog or electronics catalog without finding a reverb. Our list below proves the point!