Communist Germany aimed to control the 1960s synth market with this oddity.

Originally built by engineers working on acoustics and music interfaces in East Germany in the 1960s, the Subharchord remains one of the most unique yet forgotten synthesizers in telectronic music. Das Filter has filmed a short documentary on the synth to shine a light on its legacy and display one the the few left in action.

In the video, historian Manfred Miersch explains how the Subharchord was developed when the German Democratic Republic decided synthesizer development could be a smart economic move. Without the resources to compete with Hammond, engineer Ernst Schreiber chose to base the design on an even older electronic instrument: Oskar Sala’s Mixtur-Trautonium.

That 1930s instrument used subharmonic frequencies to create sound, an idea that the Subharchord took and expanded to achieve its singular sound. Add in other qualities like a pressure sensitive keyboard to create long attacks, and it remains a groundbreaking instrument despite its obscurity.

Watch Miersch go even deeper with the instrument and show it off below.

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