Roland TB 303
The TB-303 is a monophonic analog bass synthesizer partnered to a pattern-based step sequencer released in 1982. It has a single analog oscillator with two waveforms (ramp or square) and has a simple but brilliant VCF filter with resonance, cut-off, and envelope controls.
The TB-303 (Transistor Bass) was originally marketed to guitarists for bass accompaniment while practicing alone. The TB-303 has become one of the most in-demand vintage synths. It has helped develop and stylize many forms of electronic music including House, Acid, Trance and Ambient.