Short circuit or disconnect to bypass a compressor
I would probably do couple things:


Detach 'Equalize basses' output and ensure the level is similar to input 'Bass amplifier';
When levels are similar (either directly, or through a attenuator or simple amplifier stage) disconnect the 'Equalize basses' from 'Compressor' and connect it to 'Bass amplifier'. Notice that there is a small low pass filter in the input stage of the 'Compressor' block that probably belongs in the 'Equalize basses' block.
Connect the 'Compressor' input to ground (leave the 1uF cap in place) so it is effectively silenced. You could consider removing power from that block or removing the opamps in it.
Leave the 'compressor' output detached from the 'Bass amplifier'