Behringer MX802A Monitoring Modification

 Mikael Willberg

 24.2.2015 English, Suomi Projects · Hacking  ·

I have a small Behringer Eurorack MX 802A mixer for controlling audio volume from a computer. Most of the time I use headphones, but from time to time I need to have audio out of active speakers. Speakers are connected to Main Output and headphones to Headphone/Control room output.

The annoyance in this particular setup is that when I want to mute or change the volume of the Main Output it will mute or change the volume of the headphones. As Behringer 802A has only single bus so this cannot be solved with creative routing.

A quick Googling revealed a person with the same annoyance: Behringer MX802A Headphone Volume Hack (comcast.net)

I studied the routing diagram and PCB for a while. To properly trace the PCB would mean removing all the knobs, I decided to trust the webpage. After all it is easy to revert back to original if there would be a problem.

Modification

After implementing this modification Main Mix and Control Room & Headphones knobs will control volume independently to their outputs. Also "2TK TO CTRL R" button will be rendered useless.

I first removed R302 and R303, then soldered them to the main bus connections. Then added jumper wires from there back to the control room strip.

As an added bonus there's nice adrealine rush while working with SMC components 8-)