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.
Erica Synths Black Envelope Generator is a compact, fully analogue envelope generator with some cool bonus features like gated loop and gate delay for nice acid basslines and veeeerrryyy slow drones.
Erica Synths Pico Quant is an advanced CV quantizer with some unique features ヨ quarter tone accuracy and a web-based interface for creating user generated scales.
Erica Synths 8 channel Sequential Switch is a unique module that allows you to sequence up to eight sound sources in advanced ways or route one sound source sequentially to eight different sound modifiers ヨ VCFs, waveshapers, VCAs, etc.