This is a repost of my SSL Build Thread. Thanks to Gyraf.dk for the schematic plans.
The compressor is a clone based from the SSL4044E desk (1985 era). The SSL mixbus is actually an integrated part of the desk's main quad fader and autofade system. Click here for schematics
There's been some mods
to the original schematics for use with THAT VCAs. This page contains adjustments to the resistor values.
I also did some mods on my unit. Mainly, adding transformers at the output. Originally, the unit uses opamps for balanced outs. I have some MCI 416 output trafos that I used for my SSL unit.