Module is available as a DIY project only.
This Module is currently available.
Quad Voltage Inverter
A voltage inverter makes positive voltages into equivalent negative voltages and vice-versa. So a +2.1V input voltage will produce a -2.1V output. It can be useful for turning an LFO signal into two signal 180 degrees out of phase with each other or creating negative versions of CV signals from envelope generators.
https://www.bartonmusicalcircuits.com/4hp/4invert/index.html
These merchants probably sell this module. Huh?
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