Marshall Guv'Nor + GV-2 True Bypass Mod

[VanDerchuck]

Hello everyone. This is my first post. I've been lurking for a while, but never posted before.

Here is the question. Is it possible to mod a GV-2 for true bypass?

Here is the schematic.

http://www.fileden.com/files/2008/12/25/2237836/Marshall%20GV2%20Schematic.pdf

With new jacks and a new switch I should be able to rewire them for true bypass, I'm not sure what the components labelled L1-L5 are for, and whether I need them or not.

Would anyone like to help me out?

[alexradium]

I did some work on this, but originally this is kind of a millennium bypass, it's not electrically the same but sound wise it's similar.
Do you experience any leaking sounds in bypass?

[VanDerchuck]

I have no experience with this type of bypass at all. My first thought is to take out the board with the switch on it and vero a new one that has the pedal always engaged. Then replace the jacks and switch to wire it up with true bypass. Do you believe this is possible? I'm still not sure what the components labelled L1-L5 are, I'm going to take a picture of the board with the switch later and post it. Thank you.

[alexradium]

L1 is a ferrite for rf rejection, it doesn't alter the sound and eliminate potential noises.
I have the pedal,no need for pics.
Yes,you can make a new board with jacks and 3pdt

[slacker]

Looks fairly easy. Get rid of the jack PCB, "IP" is your effect input, "Effect" is the output, you can then use 2 sections of a 3PDT switch using normal true bypass wiring. Connect Mute, LED and -VS to the remaining part of the switch as shown on the schematic that way the original LED and muting will work without requiring any further modification.

[VanDerchuck]

That's what I was hoping for. But not knowing what a ferrite is, and having 5 of them on that board, I didn't want to rush into anything. Thanks to both of you for the help.

Skeet

[VanDerchuck]

Hopefully last question, do I need to use an input grounding wiring diagram like this one?

http://www.generalguitargadgets.com/pdf/ggg_sw_3pdt_tb_gi_bat.pdf

[slacker]

You don't need to, the grounded input method is to stop the circuit from oscillating or making any noise when bypassed. If you wire the 3PDT to use the original LED and mute circuit that should do the same job. It wouldn't do any harm if you did use it though.