Interesting and unique synthesis techniques seem to be plentiful of late, and the E‑RM Polygogo is no exception. It’s also one of a growing number of modules that are stereo, plus it may just be the best looking module I’ve ever seen.
The Polygogo uses a digital synthesis method invented by E‑RM called Polygonal Synthesis. This works by plotting the X and Y position of drawn polygons. If, for example, you draw a circle, and you plot the amplitude of one axis over time, you get a sine wave. The speed of the drawing dictates the frequency and by changing the shape and rotation, a huge variety of stereo waveforms can be generated.
A beautiful OLED yellow‑on‑black screen shows you the drawing plot and updates in real time as you change parameters. The graphics are the exact polygonal plot that is output from the X and Y (left and right) outputs. It’s hard to convey in words just how nice this screen looks, and the polygon plotting is rather mesmeric.
Most of the slider controls are focused on manipulating the polygon shapes and every parameter can be CV controlled. The knobs above each slider change from fine‑tuning controls to bipolar CV attenuators when a cable is...