Can I wire up one tone knob on a Guv'nor?

[mattpas]

On the Marshall Guv'nor pedal is it possible to use one knob for tone instead of the bass, middle, and treble knobs?
Has anyone done this and will it work?

[slacker]

Yes you can replace the tone controls with a simple tone control if you want to. The MI Crunch Box is basically a Guvnor with a Rat style tone control, a Bigmuff tone control would probably sound good too.

[mattpas]

Yes you can replace the tone controls with a simple tone control if you want to. The MI Crunch Box is basically a Guvnor with a Rat style tone control, a Bigfluffy tone control would probably sound good too.

Does anyone have a layout diagram on how to do it?

[slacker]

Are you using you're own layout or trying to fit a different tone control into an existing layout?

[mattpas]

Are you using you're own layout or trying to fit a different tone control into an existing layout?

I was going to use either General Guitar Gadgets or Tonepad for layout

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

http://www.tonepad.com/getFile.asp?id=108

[Mark Hammer]

It has not been established what sort of single-knob tone control you want.

What is available?

• The Big Muff control which pans from bass with no treble to reedy treble with no bass.
• The Rat-style variable lowpass (you can use the SWTC, which does not require a buffer stage)
• The Superfuzz/Blender/Tone-Machine/FY-2 midscoop with variable scoop depth (big bottom and sizzling top but no mids vs meaty middle)

There are others too, but these three present some options.  Take a look at some of the labnotes documents over at Jack Orman's AMZ site for some useful ideas.

Just be aware that all passive tone controls entail some degree of selective signal bleed, some with more bleed than others.  Switching over to a different tone control system may entail having a much hotter output than presently, OR a somewhat softer output.  Both are "fixable" to the extent that you feel the need to fix them.  Just know that it WILL happen and your current preferred settings may need some adapting to.

[mattpas]

It has not been established what sort of single-knob tone control you want.

What is available?

• The Big Muff control which pans from bass with no treble to reedy treble with no bass.
• The Rat-style variable lowpass (you can use the SWTC, which does not require a buffer stage)
• The Superfuzz/Blender/Tone-Machine/FY-2 midscoop with variable scoop depth (big bottom and sizzling top but no mids vs meaty middle)

There are others too, but these three present some options.  Take a look at some of the labnotes documents over at Jack Orman's AMZ site for some useful ideas.

Just be aware that all passive tone controls entail some degree of selective signal bleed, some with more bleed than others.  Switching over to a different tone control system may entail having a much hotter output than presently, OR a somewhat softer output.  Both are "fixable" to the extent that you feel the need to fix them.  Just know that it WILL happen and your current preferred settings may need some adapting to.

Sorry Mark,
I would like a tone control that has a good balance from low to high.

[Mark Hammer]

Sorry Mark,
I would like a tone control that has a good balance from low to high.

I'm not exactly sure what that means.  What do you want to be able to cut out or emphasize?

[mattpas]

I am not sure, maybe if someone could direct me to some layouts or instructions on how to do it I might get a better understanding of what I want to do.

[ConanB]

Sounds like you want one extreme of the knob to be a low bass sound, the other extreme to be a higher treble, so go with the Big Muff control. Check Jack Orman's AMZ like suggested, he has some great lab notes on the Big Muff tone control and changes you can make to it, which includes schematics etc

For example...

http://www.muzique.com/lab/dtone.htm

[ConanB]

Also in case your not sure where to add it in (now I may be incorrect here so maybe someone more experienced can correct me if I'm wrong) going by the layout/schematic on GGG where all the diodes connect to R9 and C13 you would instead remove everything from R9/C13 up untill the volume pot. Instead you would join the input of your BMP tonecontrol to where R9/C13 join and have it's output connect to lug 3 of the volume pot (where the treble used to connect).

Correct me if I'm wrong guys, I'm still new to this.

[mattpas]

I went to muzique but am still a little unsure.
I included the GGG and Tonepad layout for those who know more about this and can help me out.

[ConanB]

Ok, look at the GGG schematic and the GGG PCB layout. Be sure you realise you wont get a PCB layout with the changes you want, as your asking someone to design a PCB for you which people most likely wont do. Best to make a perfboard or stripboard layout yourself, or make the tone control on stripboard/perfboard and have a wire connect to the original PCB in the locations I mention below.

Now, looking at the schematic your removing the section that starts where it splits off to C13 and R9 until just before the Level pot, VR5. Look on the PCB and it has the parts numbered, so just dont add any of the parts within the tonestack section of the schematic.

Then, to add a single control for tone (that goes from bass to treble) you add the Big Muff PI tone control from muzique (just use the first schematic example on this page if your not sure what it's doing http://www.muzique.com/lab/dtone.htm).

To add it all you do is connect the input of the new tone control to where C13/R9 used to connect, then connect the output to lug 3 of the Level control VR5. And of course be sure to ground the parts from the Big Muff PI tone control that need to be.

I'm fairly new at this ad have just started learning sections of pedals ad how they work so I may be wrong, but I think that's right. Your best bet is to breadboard it and see how it sounds.

If nothing I said makes sense then you should probably do a little more reading up on the sections of a pedal like I have been doing.
Also do a google search for Duncan Amps Tools Tonestack Calculator. It allows you to change a few component values of various tone controls including the Big Muff PI so you can get an idea of how much bass/treble/mid your 1 knob control will have.

[ConanB]

This is what I mean...



Just make the tone control at the top of that muzique link I mentioned and have it connect to the parts I've shown.

But like I said, I could be wrong.

Just look carefully at the schematic and you'll be able to spot which section is the tone control of bass/mid/treble and you'll be able to see how you could go about replacing it.

Also to the experienced guys, if I'm right could you let me know? Would help me to know I'm on the right track with my building

[mattpas]

thanks for the help.

[slacker]

I'd try what ConanB has suggested. Basically build the pedal up to where R9 and C13 meet on the GGG schematic, then solder a wire to there and then either connect the other end to a breadboard or a scrap piece of vero or perf and try some different tone controls. There's no point doing anything too permanent until you've found a tone control you like.
You could even build the original tone controls on the breadboard or whatever and try that out, you might like it or you might find that you can just use some trim pots with the original tone controls set to a sound you like.

Once you've got a tone control that you want to use you can probably figure out a way to wire it on to the original layout rather than having to have a separate board with the tone control on. If not someone else probably can.

Out of interest why don't you want the original tone controls?