Boss is a manufacturer of effects pedals for electric guitar and bass guitar. It is a division of the Roland Corporation, a Japanese manufacturer that specializes in musical equipment and accessories. For many years Boss has manufactured a wide range of products related to effects processing for guitars, including "compact" and "twin" effects pedals, multi-effect pedals, electronic tuners and pedal boards. In more recent times, Boss expanded their product line by including Digital Studios, rhythm machines, samplers and other electronic music equipment.

The earliest Boss product was called B-100 The Boss, released in 1974. This came with a clip-on pre-amp and a pickup to amplify acoustic guitars. At this point the Boss company had not been formed and it was still technically a Beckmen Musical Instruments product (as seen on the B-100 box). The first proper Boss foot pedal effect, the CE-1 Chorus Ensemble, was released June, 1976, which was a stand-alone unit of the chorus/vibrato circuit found in the Roland JC-120 amplifier. It was a fairly large, AC-powered unit. Other foot pedals of that year are the GE-10 (a graphic equalizer), the BF-1 (a flanger unit) and the DB-5 (a distortion unit).

All Boss compact pedals use a "buffered bypass" type of silent foot switching utilizing Field Effect Transistors (FETs) to avoid clicks and pops. The buffered bypass has the advantage of preventing signal loss due to long runs of cable, while keeping original guitar tone intact.

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