In my experiments with the ER-1, I always thought that its 4 VCOs would lend themselves well to rendering a fugue, and in a brief moment of joblessness I composed one (plus an accompanying prelude later on). The difficulty in having the ER-1 play it is that, being a drum machine, it was never intended to play pitched tones in any conventional way. Each VCO is fixed to a single MIDI note, and pitch can only be modulated via its 0-127 pitch parameter. In order to realize any kind of score on the ER-1, I needed to painstakingly map frequencies (corresponding to 12TET pitches) to combinations of the ER-1’s ‘pitch’, ‘modulation speed’, and ‘modulation depth’ parameters. With that mapping in place, I wrote a python script that can parse .musicxml files and translate them to the ER-1. The resulting pitches are never squarely “correct” in 12TET, an effect that I like given the tuning practices in place at the time when Bach was writing the Well-Tempered Clavier.

I had the pleasure of performing this piece live with the MDBQ in our last show, November 2025.