Effects unit

They may also be built into guitar amplifiers, instruments (such as the Hammond B-3 organ), tabletop units designed for DJs and record producers, and rackmounts, and are widely used as audio plug-ins in such common formats as VST, AAX, and AU.

Rackmount devices saw a heavy usage during the later 20th century, due to their superior processing power and desirable tones as compared to pedal-style units.

Complex stompboxes may have multiple footswitches, many knobs, additional switches or buttons that are operated with the fingers, and an alphanumeric LED display that indicates the status of the effect with short acronyms (e.g., DIST for "distortion").

[12] It is common to put compression, wah and overdrive pedals at the start of the chain; modulation (chorus, flanger, phase shifter) in the middle; and time-based units (delay/echo, reverb at the end.

[17] Rackmount effects units are most commonly used in recording studios and front of house live sound mixing situations.

Musicians may use them in place of stompboxes, as use of a rack can offer space for conveniently mounting additional rackmount equipment or accessories.

Digital effects designed for DJs are often sold in tabletop models, so that the units can be placed alongside a DJ mixer, turntables and scratching gear.

For example, on some lower- to mid-priced bass amplifiers, the only control on the audio compression effect is a button or switch to turn it on or off, or a single knob.

Microphones placed in echo chambers with specially designed acoustic properties simulated the sound of live performances in different environments.

[27] Most stand-alone effects of the 1950s and early 1960s such as the Gibson GA-VI vibrato unit and the Fender reverb box, were expensive and impractical, requiring bulky transformers and high voltages.

The first popular stand-alone was the 1958 Watkins Copicat, a relatively portable tape echo effect made famous by the British band, The Shadows.

[33] Among the first musicians to experiment with distortion were Willie Johnson of Howlin' Wolf,[33] Goree Carter,[34] Joe Hill Louis,[35][36] Ike Turner,[37] Guitar Slim,[38] and Chuck Berry.

The first transistorized guitar effect was the 1962 Maestro Fuzz Tone pedal, which became a sensation after its use in the 1965 Rolling Stones hit "(I Can't Get No) Satisfaction".

[45][46] Warwick Electronics manufactured the first wah-wah pedal,[47] The Clyde McCoy, in 1967 and that same year Roger Mayer developed the first octave effect, which Jimi Hendrix named "Octavio".

[48] Upon first hearing the Octavia, Hendrix reportedly rushed back to the studio and immediately used it to record the guitar solos on "Purple Haze" and "Fire".

[53] Throughout the 1990s, musicians committed to a lo-fi aesthetic such as J Mascis of Dinosaur Jr., Stephen Malkmus of Pavement and Robert Pollard of Guided by Voices continued to use analog effects pedals.

Nine Inch Nails, Pink Floyd, George Harrison, They Might Be Giants and Joy Division are among the many musicians who have referenced effects units in their music.

[56] Distortion, overdrive, and fuzz effects units add a warm, gritty, or fuzzy character to an audio signal by re-shaping or clipping it, which distorts the shape of its waveform by flattening its peaks, creating warm sounds by adding harmonics or gritty sounds by adding inharmonic overtones.

A fuzz pedal, or fuzzbox, is a type of overdrive effects unit that clips a signal until it is nearly a squarewave, resulting in a heavily distorted or fuzzy sound.

Noise gates are expanders—meaning that, unlike compressors, they increase the dynamic range of an audio signal to make quiet sounds even quieter.

A chorus effect splits the audio signal and adds a slight delay and frequency variations or vibrato to one version while leaving the rest unaltered.

[85][86] Some famous uses of flanger effects include "Walking on the Moon" by The Police, the intro to "Ain't Talkin' 'Bout Love" by Van Halen, and "Barracuda" by Heart.

Slicer: Combines a modulation sequence with a noise gate or envelope filter to create a percussive and rhythmic effect like a helicopter.

One early technique for creating a reverb effect was to send an amplified signal of the music via a speaker to another room with reflective surfaces, such as a tile bathroom, and then record the natural reverberations that were produced.

EBow is a brand name of Heet Sound Products, of Los Angeles, California, for a small, handheld, battery-powered resonator.

Other handheld and mounted guitar and bass resonators have been on the market since the early 1990s, produced in Germany under the SRG brand, which ceased production in 2016, and were available in both monophonic (one string at a time) and polyphonic (multiple strings at a time) models, which included multiple onboard trigger switch effects, such as HPF (high pass filter) for enhancing harmonics and producing feedback effects, and LPF (low pass filter), producing a bass boost with a cello sound on heavy gauge strings.

[115] This, combined with heavy distortion and the close proximity of the guitar and the speaker cabinet, can lead to infinite sustain at higher volumes.

Effects types include pitch shifting, distortion, filtering, wah-wah, tremolo, flanging, delay, reverberation, auto-panning, gating, phasing, and ring modulation.

Upright bassists in jazz, folk, blues and similar genres may use a bass preamplifier, a small electronic device that matches the impedance between the piezoelectric pickup and the amp or PA system.

[121] They are often more expensive than mass-produced pedals[122] and offer higher-quality components, innovative designs, in-house-made knobs, and hand-painted artwork or etching.