Erica Synths Black VCO Expander essentially is an advanced waveform mixer plus two octaves down suboscillator, it allows you to explore wave design in brand new areas.
Features
 
Waveform mixer/inverter
Sine/Triangle/”Tits” waveform switch
Transistor-based -2 octave suboscillator
-1 and -2 octave suboscillator crossfade
Suboscillator lowpass filter
Diode limiter on output signal amplitude
Three simultaneous outputs
 
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