effects pedal

effects pedal, electronic device, operated by foot, that enhances, distorts, or otherwise alters electrical signals that are transmitted through it and that originate with a musical instrument. Effects pedals are used to change the sound of the instrument, and there are numerous types. Most are typically used in setups with electric or electronic instruments, such as the electric guitar, the electric bass, and the electronic keyboard, though they can be connected to any instrument supplied with a device that converts vibrations into electrical signals, such as a microphone. An effects pedal is controlled by stepping on it, enabling the musician to dictate when an effect is switched on or off.

Portable floor-based effects pedals became available in the 1960s, following the development of the transistor. Such stand-alone pedals replaced older approaches to adding effects to music, which made use of such technologies as echo chambers and vacuum tubes, the latter having been built into amplifiers. Modern effects pedals incorporate solid-state electronics or digital components into their design in order to manipulate electrical signals via analog or digital processing. Effects pedals are plugged into the instrument’s signal path, generally being placed between the instrument and an amplifier. Often, multiple effects pedals are used, being arranged to form a pedal chain (commonly situated on a flat pedalboard that rests on the floor). In some cases, an effects loop is also created, in which certain types of pedals that modulate effects are placed after the amplifier in the signal path.

Effects pedals provide musicians with significant control over their sound, affording them many opportunities to personalize that sound, particularly when multiple pedals are used. Guitarists, for example, often have extensive pedal setups that incorporate volume pedals and compressor pedals to control loudness and dynamics (variation in the loudness at which notes are played), wah-wah pedals to filter tone, pitch-shifter pedals to modulate pitch, and overdrive and distortion pedals to alter gain (the amount by which an audio signal is amplified). Pedals to modulate effects, such as reverb (a succession of echoes), chorus, and flanging (combining two identical audio signals so that a slight delay is applied to one and the delay time is continuously varied), are usually placed in an effects loop.