Bass effect

Bass effects are electronic effects units that are designed for use with an electric bass and a bass amplifier, or for an upright bass and a bass amp or PA system. Bass effects are commonly available in stompbox-style pedals, which are metal or plastic boxes with a foot-operated pedal switch or button which turns the effect on and off. Most pedals also have knobs to control the tone, volume and effect level. Some bass effects are available in 19" rackmount units, which can be mounted in a road case. As well, some bass amplifiers have built-in effects, such as overdrive or chorus.

Fuzz bass, also called "bass overdrive" or "bass distortion", is an effect which produces a buzzy, distorted, overdriven sound, which the name implies in an onomatopoetic fashion. Overdriving a bass signal significantly changes the timbre, adds overtones (harmonics), increases the sustain, and, if the gain is turned up high enough, creates a "breaking up" sound characterized by a growling, buzzy tone. By the mid- to late-1960s, a number of bands began to list "fuzz bass" in addition to "electric bass" on their album credits. Two well-known examples are the Beatles' 1965 song "Think for Yourself" (from Rubber Soul) and the 1966 Rolling Stones song "Under My Thumb". Album or performance credits for fuzz bass can be found from every decade since then (see examples below).

Fuzz bass can be produced by overloading a bass amp's tube or transistor preamplifier, by using a bass fuzz or bass overdrive effect pedal, or for the most powerful effect, by combining both approaches. In the 1960s and early 1970s fuzz bass was associated with psychedelic music (e.g., Edgar Broughton Band), progressive rock (e.g., Genesis), and psychedelic soul/funk (e.g., Sly and the Family Stone) styles, and it tended to be a "warmer", "smoother", and "softer" overdrive-type sound caused by soft, symmetrical clipping of the audio signal which "round[ed] off the signal peaks rather than razor-slicing" them and filtered out the harsher high harmonics.

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