This video, via Synth Keith, takes a look at an early version of the rare Sequential Circuits Model 800 step sequencer.
The Model 800 is a control voltage + gate sequencer can sequence up to 256 events.
The video highlights the internal differences in the early serial number Model 800 sequencers, compared to the later ones. The most significant difference is a 10-bit DAC, which allows interfacing to Hz/V synths like the Korg MS-20 (Mini) or the Yamaha CS series.
The Sequential Circuits Model 800 was advertised along with a Model 700 programmer:
For a look at the Model 800 step sequencer in action, see the demo video below:
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