AR4 solderpads and hacks



The AR4 quad AR envelope generator has some solderpads that you can use to change some functions on it.

Disable the 1K output resistor

On the bottom side of the PCB there are 4 solder-switches near the jacks.
By soldering a short for any of these solder pads, you can eliminate the 1K output resistor for that jack.
The OP’s used for this module is LM358 that has built in short-circuit protection on the outputs.
Therefore, it is possible to do this hack if you need, but it is still better to leave the 1K resistors working as default for extra protection.

  • SJ2 – AR1
  • SJ1 – AR2
  • SJ5 – AR3
  • SJ7 – AR4

Maximum output range

Each output has a voltage divider on the output to lower the maximum output level.
If you want maximum level outputs, you can solder the following solder pads to bypass the voltage divider.

  • SJ3 – AR1
  • SJ4 – AR2
  • SJ6 – AR3
  • SJ8 – AR4