One thing which surprised me was that there seems to be at least two different version of VMX100: One that uses a THAT2164 VCA for crossfader and one that doesn’t. I’m not sure which one is the older model, but it’s a clear move by Behringer to make the mixer even cheaper to manufacture by reducing the parts count. The various sections on VMX100 main board. So that’s a good number of sections to mess around with! Toward bottom right corner there’s what I assume to be the main output gain opamp. On the main board and moving from edges towards the center, there are the channel preamp / EQ stages (Ch.1 left / Ch.2 right), followed by headphone monitoring knobs (top left), output gain knobs (top right) and level / tempo LED indicators to the center. The regulators are installed on a smaller daughterboard, which also hosts input/output RCA jacks and the phono input preamp. Of course provided that no specific reference voltages are used. opamps should run pretty fine on the +/12VDC of Eurorack format without any changes.

This is good in that for the most part eg. On the PSU side the VMX100 has a bog-standard linear PSU setup implemented with 78xx / 79xx series regulators which output +/-15VDC and +5VDC. This is good in that it allows cutting the main board into a number of smaller boards so that they actually fit the Eurorack format. Taking a quick peek inside VMX100, in overall its PCBs are very clearly compartmentalized (is that even a real word?). So the solution: I’ll mess around with the boards and see what I end up with. However now I had a second VMX100 with quite a few more spare parts left than what I would need. The electronics were working fine and it felt like a waste to just toss the rest.

Behringer vmx100