This is a schematic for a modified version of the Dan Armstrong Orange Squeezer compressor. All of the mods came from a discussion at DIY Stompboxes. The original objective was to optimize the circuit for bass guitar by replacing the half-wave rectifier with a full-wave rectifier, among other mods as noted on the schematic.
I have not built this circuit, myself. But there have been a number of reports at DIY Stompboxes over the years. Reviews are mixed. Some feel that the stock version of the Orange Squeezer is as good as it gets.
Anyway, here’s the schematic (click for bigger). NB: R1 should be 4M7.