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this auction"The Roland TR-909 Rhythm Composer is a partially analog, partially sample-based drum machine built by the Japanese Roland Corporation in 1984. It features a 16-step music sequencer and a drum kit that, at that time, aimed for realism and cost-effectiveness. It is fully-programmable, and like its predecessor, the TR-808, can store entire songs with multiple sections, as opposed to simply storing patterns. Only around 10,000 units were produced.
The drum machine is in perfect operating condition, all knobs work and buttons properly trigger drum sounds. Some drum sound knob pots are scratchy which is common with a synth of this age but can easily be cleaned or have knob pots replaced. Once you set the drum sound you want, and stop moving the knob, the sound output is loud and clean."