The TB-303 was a synthesizer/sequencer produced by the Roland corporation in 1982 and 1983 that had a crucial role in the development of contemporary electronic music. The TB-303 (named for "Transistor Bass") was originally sold to guitarists for bass accompaniment when practising alone, a role in which it failed miserably. Production lasted approximately 18 months, resulting in 20,000 units. It wasn't until the mid- to late-1980s that DJs and musicians in Chicago found a use for the machine in the context of the newly developing house music. Phuture's "Acid Trax " is widely acknowledged to have been the first track to incorporate the sounds that have come to define the sound the TB-303 is known for today. The well-known "acid" sound can be produced with a TB-303 by playing a melody while changing the cutoff frequency, resonance, envelope modulation, and accent controls. (The accent control modified the note volume, resonance, and envelope modulation.)
The unit had a single oscillator (set to either sawtooth wave or square wave by a switch), a simple envelope generator (with decay control only), and a lowpass filter with -18 dB per octave rolloff (with controls for cutoff frequency, resonance, and envelope amount).
It also featured a 'simple' step-time method for entering note data into the 16-step programmable sequencer. This was notoriously difficult to use, and would often result in entering a different sequence than the one that had been intended - some users also take advantage of the quirky fact that when the batteries are removed for a certain period, patterns that are programmed in memory begin to vary in random ways - one of the factors that helped to create the randomish acid sound.
Roland's designer of the TB-303, Tadao Kikumoto, was also responsible for the well-known TR-909 ("Transistor Rhythm").
List of musicians who use the TB-303