|NEA_5F4019_VCA_Build_Notes_and_User_Manual.pdf||NEA-4019 Discrete VCA User Manual & Build Notes
Thank you for purchasing an NEA-4019 VCA module. This module is an adaptation of the ARP 4019 VCA
found in the ARP 2600 synthesizer using . This document will provide information about the basic
functions of the module, build notes, as well as the trimming procedure.
The red stripe on the power cable is always -12V. Be aware of the orientation of this cable. The cable
and the PCB header are keyed to avoid accidentally plugging the power cable in backwards. The VCA has
a red LED indicator on the rear PCB to indicate that the module has successfully powered up. If you do
not see this LED lighting up, there is a problem and you should disconnect power immediately.
Front Panel Jacks
Audio Input 1 & 2 - These are the signal inputs of the VCA. Although they are labeled as audio inputs, DC
signals can be amplified as well. There may be slight DC offsets when using the VCA to amplify DC
signals. Audio input 1 in non-inverting, and audio|