Quadigy - Quad Envelope
Klavis Quadigy - Quad Envelope 2 Colors
Javelin - Envelope and VCA
WMD Javelin - Envelope and VCA
Malekko Heavy Industry Quad Envelope
Quadrax
Pons Asinorum - Quad LFO/Envelope
Contour (Black)
Envy Machine - Quad Envelope Modulation Monster
Airstreamer 4 - Envelope Generator
Intellijel Quadra
Intellijel Quadra Expander
Doepfer A-143-1 Quad AD-Generator
XAOC Devices Batumi