The Roland TB-303 Bass Line (also known as the 303) is a bass synthesizer released by Roland Corporation in 1981. Designed to simulate bass guitars, it was a commercial failure and was discontinued in 1984. However, cheap second-hand units were adopted by electronic musicians, and its "squelching" or "chirping" sound became a foundation of electronic dance music genres such as acid house, Chicago house and techno. It has inspired numerous clones.

The TB-303 was manufactured by the Japanese company Roland. It was designed by Tadao Kikumoto, who also designed the Roland TR-909 drum machine.^[1] It was marketed as a "computerised bass machine" to replace the bass guitar.^[2] However, according to Forbes, it instead produces a "squelchy tone more reminiscent of a psychedelic mouth harp than a stringed instrument".^[3]

The TB-303 has a single oscillator, which produces either a "buzzy" sawtooth wave or a "hollow-sounding" square wave.^[3] This is fed into a 24 dB/octave^[4] low-pass filter, which is manipulated by an envelope generator.^[2] Users program notes and slides using the internal sequencer.^[3]

The TB-303's unrealistic sound made it unpopular with its target audience, those who wanted to replace bass guitars. It was discontinued in 1984,^[5] and Roland sold off remaining units cheaply. 10,000 units were manufactured.^[3]

The first track to use the TB-303 and enter the top ten of the UK Singles Chart was "Rip It Up" (1983), by the Scottish band Orange Juice.^[6] Charanjit Singh's 1982 album Synthesizing: Ten Ragas to a Disco Beat was another early use of a TB-303, alongside another Roland device, the TR-808 drum machine. The album remained obscure until the early 21st century, when it was reissued and recognized as a precursor to acid house.^[7]

The Chicago group Phuture bought a cheap TB-303 and began experimenting. By manipulating the synthesizer as it played, they created a unique "squelching, resonant and liquid sound". This became the foundation of the single "Acid Tracks", which was released in 1987 and created the acid genre. Acid, with the TB-303 as a staple sound, became popular worldwide, particularly as part of the UK's emerging rave culture known as the second summer of love.^[3]

In the late 1980s and early 1990s, as new acid styles emerged, the TB-303 was often overdriven, producing a harsher sound, such as on Hardfloor's 1992 EP "Acperience" and Interlect 3000's 1993 EP "Volcano".^[8] In 1995, the TB-303 was distorted and processed on Josh Wink hit "Higher State of Consciousness"^[4][9] and on Daft Punk's "Da Funk".^[10]

In 2011, the Guardian named the release of the TB-303 one of the 50 key events in the history of dance music.^[5] The popularity of acid caused a dramatic increase in the price of used 303 units.^[3] As of 2014, units sold for over £1,000.^[11]

The TB-303 has inspired numerous software emulations and clones,^[12] such as the TD-3 by Behringer, released in 2019.^[13] In 2014, Roland released the TB-3 Touch Bassline, with a touchpad interface and MIDI and USB connections.^[14] In 2017, Roland released the TB-03, a miniaturized model featuring an LED display and delay and overdrive effects.^[15]