The Roland MC-307 is a combination of MIDI music sequencer, synthesizer, drum machine and control surface produced by the Roland Corporation.
It does, however, have several features that make it an ideal clock source for musicians wanting to do beatmatching.
These include a large, very granular tempo slider similar to the sliders found on a modern phonograph and 'push' and 'hold' buttons that permit temporarily slowing down or speeding up the beat clock.
It can also transmit MIDI Machine Control and MIDI beat clock, and slave to external beat clock sources such as other Roland grooveboxes.
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