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 #81755  by mkaufman
 Sat Jun 12, 2010 6:54 am
I have given my poor man's Cowboy to someone for final preparation. It has 3 pickups, each with its own on/off toggle. I want each pickup to have it's own volume control, plus a master tone control. The tech can't get it working as there's some crazy interaction between the volume pots. To be fair, I had the same issue!

As an alternative, I'd consider using 3 small trim pots (instead of individual volume pots) with a master volume and a master tone pot a la the true Cowboy. The trim pots would be accessible through the backside of the control cavity cover plate.

With the real Cowboy, after the signal passes through the trimpots, it goes through a circuit board and the active electronics, which I don't have.

How can I get this to work? I've looked at the "50's Gibson wiring" technique which supposedly yields two independent volume controls, however, this technique uses 2 tone controls. I'm not sure if this will work. In general, I wouldn't think this would be so hard. Can anyone help?

tnx,
mk
 #81765  by mkaufman
 Sat Jun 12, 2010 10:51 am
Thanks, but I'm pretty sure there are significant differences between this diagram and what I need. I think with this diagram, the middle pickup and associated volume pot are always engaged. I'm not sure why, however, I think it makes a difference.

mk
 #81768  by JonnyBoy
 Sat Jun 12, 2010 12:10 pm
you can wire it the same way and run them through DPDT switches to turn off whichever signal you want before it gets to the vol pot or even after. I think that scheme is the way all les pauls are wired, straight from the pkups to the volume pot then to the switching, or a slight variation of that. If you have the right type of switch for a pickup selector it should disable the other non used pickups. you may need a 5 way switch. I don't know how the middle is still running if the switch doesn't allow it to connect into the circuit?
 #81776  by drewfx
 Sat Jun 12, 2010 3:50 pm
The key is which lug you wire to the PU and which goes to the output.:

1. If you wire PU to outside lug, output to center, then the volume controls will interact like a Les Paul does - if you turn one PU all the way down on an LP you get no sound from either PU in the center switch position.

2. If you wire PU to center lug, output to outside lug, the volumes don't interact.

(Note that in both cases, I'm talking about the outside lug not wired to ground.)

So I would go: (each) PU -> center lug of volume & outside lug of vol -> toggle -> output (with tone hanging off output).

I'm a little concerned that your tech couldn't figure this out though...
 #81812  by mkaufman
 Sun Jun 13, 2010 6:35 pm
Scott - that was incredibly generous of you! Tom must have mentioned something to Joseph about you owning a Cowboy. I knew nothing about any of this.

Anyway, I have the Cowboy schematic and gave a copy to Joseph. Each pickup passes through a trim pot and then into the EQ/Pre-amp circuit card and then there's one master volume & master tone pot. I suspect the 'magic' that allows the trim pots not to interact with eachother happens in the circuit board itself, therefore, I'm not sure if Joseph will see anything obvious.

I'll let you know!

Thanks so much!

mk