Living Colour’s Doug Wimbish is a master of expression pedals, and he uses them to subtly—or extremely—alter tones
of his effects while he plays his bass. Photo by Mike Marques

The earliest expression pedals had a problem. They were extremely difficult to use. Operating the pedal with your foot required far too much effort. The pedals were difficult to control, in either direction, pressing or releasing. But don’t let that discourage you from using one today—those first versions appeared a little over 300 years ago.

The term expression pedal refers to any device that can alter aspects of sound from an instrument by a continuous-action, foot-operated movement. Volume is an obvious one. Tone is another. And as you’ve just learned, it is by no means a recently coined term.

Organ-ic Developments
If you’ve ever played a pipe organ, you know that your hands don’t control the power behind a note. Hitting a key on the keyboard soft or hard makes no difference. The power is generated independently by a device pumping air to the pipes. Each key releases a valve in a pipe.

Organists in the early part of the 18th century had no control at all over volume. A British craftsman named Abraham Jordan devised a solution in 1712. While pipe organs didn’t have volume controls, some did have an echo feature. Of sorts. Organs were fitted with a second set of treble pipes, aka stops, enclosed in a box to simulate a more distant echo-like sound. Jordan’s idea was to add shutters to that box. The organist stepping on a pedal, which lifted or lowered the shutters, operated them. The effect was called “swell”—an increase in volume that was sure to send chills down the spines of holy and not-so-holy churchgoers at the time. The result was dramatic, and churches around Europe quickly modified their organs’ echo boxes in a likewise manner to adopt the swell effect.

Jordan’s original version of the pedal wasn’t a great design. It worked, but excessive force was needed to operate it. Fifty or so years later came a simple but significant improvement. Builder Samuel Green fitted a pipe organ with a “Venetian style” swell, adopted from harpsichord designs, which was easier to control. As the name implies, this was a Venetian-blind type of arrangement. The pedal controlled the angle of a series of parallel slats on the echo box. In either form, the result in volume was analogous to opening and closing the upper lid on an upright piano: The pedal either kept the sound in or let the sound out. So for some instruments, expression pedals have given musicians the ability to modify sounds using their feet for quite some time.

6-String Theory
For electric guitars, expression pedal history doesn’t go back nearly as far, although we can find strong connections to organs. Patents for volume controls on organs date to the late 1800s. By the early half of the 20th century, the Hammond Organ Company was equipping electric organs with pedals that could easily be adapted to guitar. For use with guitars specifically, DeArmond offered a freestanding foot pedal for volume control in the 1940s, to accompany pickups in their product line.

D’Armond’s dual-purpose 610 pedal, which controlled volume and tone, was the opening salvo in the expression pedal revolution for electric guitar.

Pushing expression capabilities even further, the patent for Harry DeArmond and Leonard Meeker’s 610 pedal for DeArmond/Rowe Industries dates to 1958. It wasn’t exactly what you would consider a wah-wah pedal, but it was a dual-purpose pedal. Built like a tank, the foot pedal’s up-and-down movement controlled volume, while side-to-side movement modified the tone. The result of these two basic features was identical to adjusting the volume and tone knobs on a guitar, but using your foot, of course, meant you could make those adjustments while still playing.

Guitarists learned to use the new foot-borne capability. Peter Van Wood used a Hammond pedal in 1955 to record an instrumental version of “Summertime,” the George Gershwin classic, with his Gretsch archtop.

To hear the DeArmond 610 volume-and-tone control, specifically, in action, listen to Big Jim Sullivan’s guitar on Michael Cox’s recording of Chuck Berry’s “Sweet Little Sixteen.” Or his work on Dave Berry’s “The Crying Game.” (Also on the latter recording, you’ll hear Jimmy Page on acoustic guitar. The moniker “Big Jim” differentiated the two session players.)

Following these, the wah-wah is the next most widely recognized example of an expression pedal. The Thomas Organ Company, in agreement with Jennings Musical Instruments of England, manufactured solid-state (and some tube) versions of Vox amps and keyboards in the U.S. In 1966, Bradley Plunkett of Warwick Electronics, the parent company of Vox and Thomas Organ, added a potentiometer to the MRB circuit (Mid Range Boost) being used on the Vox Continental organ. When that circuit moved into the housing of a Vox organ volume pedal, a whole new kind of expression for guitarists took off. Sounding like a mute on a trumpet and named after trumpet player Clyde McCoy, the wah-wah entered guitar history.

The Uni-Vibe also had an early start. The device was first developed by Shin-ei in Japan under the name Vibra Chorus, and quickly rebranded in the mid ’60s as the Shiftee Uni-Vibe as it reached Western markets. It emulated a Leslie speaker cabinet’s unique Doppler effect and used a 5-pin circular DIN connector for a foot controller.

With all sorts of new effects pedals making their appearance in the late 1960s and on through the ’70s and ’80s, it’s a wonder that the idea of expression-pedal-ready effects didn’t catch on sooner or become more widespread. But today expression pedals, in use with many types of effects, are rapidly gaining popularity.