The Amp Feature Nobody Asked For: How a Chorus Circuit Left the JC-120 and Became the Boss CE-1

Some of the most recognisable guitar tones began as a feature on a product sold for another reason. In 1975 Roland launched the JC-60 and JC-120 Jazz Chorus amplifiers, built around a clean, solid-state sound and a stereo chorus circuit. A year later the company lifted that circuit out of the amp, put it in a heavy die-cast box, and called it the Boss CE-1 Chorus Ensemble. The first chorus pedal was, in effect, an amp feature set free.

What Chorus Actually Does

The idea is simple. Take the guitar signal, delay it by a few milliseconds, wobble that delay slowly, and blend it with the dry signal. The tiny pitch drift between the two copies reads to the ear as several instruments playing almost together. One description of the effect calls it a modulated, slightly delayed copy mixed with the original, and traces it to 1970s experiments with short delays and slow pitch modulation.

What made a compact version possible was the bucket-brigade device, a chip that passes a signal along a chain of small steps. According to one technical history of the pedal, the CE-1 used a Matsushita MN3002 chip, with Roland reportedly the first customer for Matsushita’s licensed version of the Philips design.

A Pedal That Looked Like Studio Gear

The CE-1 was not a pocket pedal. It ran on mains power, came in a large metal case and carried two footswitches, level and intensity controls, and separate vibrato rate and depth. It offered stereo outputs, which meant a guitarist could feed two amps and get a wide, shimmering image from one instrument. Chorus and vibrato shared one chip, so you chose one or the other, never both at once.

It was also expensive. A history of Boss chorus pedals reports that sales started slowly because of the price, then rose once players discovered the stereo output with multiple amps. Production reportedly continued until about 1984.

The Sound of a Police Record

The name most tied to the sound is Andy Summers of The Police, whose playing on Message in a Bottle, Don’t Stand So Close to Me and Walking on the Moon is usually cited as the textbook use of the CE-1. His guitar sits in a space between rhythm and texture, with the chorus doing the work a second guitarist would normally do. A trio sounding that wide was exactly the point.

Summers is also linked with the JC-120 itself, which tells you how closely the amp and the pedal share a lineage.

Smaller, Cheaper, Everywhere

In October 1979 Boss released the CE-2, a compact pedal using the same circuit but dropping the vibrato, stereo outputs, level and intensity knobs and built-in power supply. It was affordable, easy to use with only rate and depth, and it is described as the first compact chorus pedal. The CE-3 followed in 1982 with stereo output restored.

In 1979 Roland also released the SDD-320 Dimension D, a rack unit with four preset buttons and no rate or depth controls, designed for subtle widening rather than obvious motion. The same company, within a few years, had sold the guitar world both the pedal and the studio version of the idea.

Why It Still Matters

The CE-1 story is a reminder that gear history often runs backwards from how we tell it. The effect was not designed as a rock pedal. It was part of an amp aimed partly at keyboard players, and guitarists claimed it. Every modern chorus on a pedalboard, in a plugin or in an amp simulation is a descendant of that decision to unbolt a circuit and sell it separately.