Andromeda Space Rockers MK-2 Synth Pulse Kit

This was designed as an experiment of making the most minimal drum machine possible using analog circuitry.  Beyond that goal, the design also includes a new feature, IR Sync, which allows a group of these units to all synchronize together and play at the same tempo automatically.  Although the sound of one Andromeda MK machine alone is simple, a group of them together can play more complex rhythms.  The complexity of the patterns is multiplied with each additional unit that is added to the network.  A maximum of 12 units can be connected in a chain.

The Andromeda MK2 analog drum machine has a minimal sequencer with sixteen preset patterns, selectable by the red switch block.  The pushbutton restarts the patterns.  This feature allows you to shift the timing of the rhythm when synchronized with other Andromeda Space Rockers instruments.The sound of the MK2 is from an analog white noise generator.  This noise is filtered by a resonant filter, and the cutoff of the filter is controlled by the photocell on the left side of the unit.

The sequencer triggers an envelope generator (EG).  This creates a signal that controls the duration and volume contour of the sound.  The EG is controlled by the photocell on the right side of the unit.

The EG’s signal is sent to a voltage controlled amplifier (VCA).  The VCA chops up the steady output from the filtered white noise generator into little bursts of sound, controlled by the EG.  This is what you hear at the output.