The Sputnik Modular West Coast Random Source (WCRS for short) is a very capable Eurorack-format update on the classic Buchla Source of Uncertainty module. It is perhaps best known for its Fluctuating, Quantized, and Stored Random Voltages, which are what set it apart from a typical “random source” module. However, it also has a traditional Sample & Hold, paired with 1:2 switches to create alternating triggers and sampled voltages.

In the movie below, I focus first on uses for those 1:2 switches, including using them to send alternating note-on gate or triggers to alternating drum sounds (an Erica Synths Pico Drums), and then to two different envelope generators (both in a Roland 540 dual ADSR) to get different articulations on successive notes. Aside from simple, obvious “1 2 1 2 1 2” alternations, this can also be useful for more subtle applications such as mimicking drum strokes from two different hands, or the alternating up stroke and down stroke of fast guitar pick technique.

Then I move on to showing the sample and hold itself, first with the typical “science fiction soundtrack” random pitch technique, and then for something more subtle such as randomly changing the pulse width of the Moog Mother-32’s VCO on each successive gate or trigger in to add variation to each note played. In this case I used the Sputnik’s blue noise output as my voltage to sample on each trigger, as it has a wider voltage range than the WCRS’s pink and white noise; the Moog’s noise output has an even wider range. I also used the Sputnik’s Integrator to smooth out the random voltages; note that even at its minimum setting, it is always performing some smoothing – so patch around it if you want sudden voltage changes.

This is the fourth of four movies on the West Coast Random Source from my Learning Modular Synthesis: European Expansion course. The first movie is a general overview of the module, including listening to the different noise types. The second explores the Fluctuating Random section of the WCRS (my favorite alternative to LFO modulation), while the third explores the Quantized & Stored Random sections (great for “controlled” S&H type patches).