unfamiliar with schematics

[abr_eu]

i don't understand how to wire this bypass,
it seems simple enough, but i've never seen it like this.

could anyone enlighten me please?

many thanks

[Voltzy]

Could you post the rest of the schematic so we can understand what is going on?

[Rob Strand]

You will find when the switch is closed it grounds that point.  The opamp will be configured with high gain and you get overdrive.   When that point is disconnected from ground the opamp will be configured as a unity gain buffer and the circuit elements related to overdrive are disabled.    The key is to realize all the junk in the feedback path has no effect when the path from the opamp - input to ground is removed.

Other forms of this type of bypass might also switch the output clipping diodes off the ground rail.

Peavey and many combo amps use this type of thing for an overdrive switch.

[abr_eu]

Could you post the rest of the schematic so we can understand what is going on?

Sorry, the schematic has a "copyright" disclaimer so i figured this would be enough

You will find when the switch is closed it grounds that point.  The opamp will be configured with high gain and you get overdrive.   When that point is disconnected from ground the opamp will be configured as a unity gain buffer and the circuit elements related to overdrive are disabled.    The key is to realize all the junk in the feedback path has no effect when the path from the opamp - input to ground is removed.

Other forms of this type of bypass might also switch the output clipping diodes off the ground rail.

Peavey and many combo amps use this type of thing for an overdrive switch.

Thanks, this sounds simple in my head. I'll try it when i can and see if it's as clear as it sounds.