2x Volume and 2x Tone problem

[badboy1984]

My bass originally is a Precision bass with 1x volume and 1x tone. I have modded to make the bass become P/J bass with 2x volume (stacked) and 1x tone. Ideally I liked 2x stack pots for the bass so each stack control the volume and tone for that particular pickup so the p and j pickup will have individual volume and tone.

After many weeks my guitar tech I always goes to finally source the correct part to make this work and the bass look and sounded fantastic. I realise one problem when I tried it out last night.

First the volume for each pickup works correctly but the tone does not. For example if I solo the bridge pickup by turning the p volume down the p pickup tone still engage. So that means if I turn the p pickup tone down it cut the treble off when I solo the bridge pickup. What makes it interesting is the bridge pickup tone can also work at the same time to cut even more treble. This means I now have 2x master tone ......

I'm still wondering shall I take it back and get it fix or 2x master tone actually work better?

Edited June 23, 2014 by badboy1984

[Monckyman]

Yes, you should have separate tone controls for each pickup.

[Beer of the Bass]

You may have to wire it like a Stack-knob Jazz bass with resistors (220k, iirc) between the volume controls and the output to prevent the tone controls interacting. This will lose you a little output, which may have been one of the reasons Fender moved away from the stacked knobs. Alternatively you could install a selector switch and wire it like a Les Paul. The two tone controls would still act like master tone controls when both pickups are on, but you can solo pickups using the switch and not lose any output.

[BigRedX]

Putting the tone controls before the volume controls in the circuit should cut down the amount of unwanted tone interaction.

[badboy1984]

Hmm, doesn't seem to bother me that much because I'm full on most of the time but sometimes I do use the tone to cut some treble on certain songs. It just interesting the guitar tech wire it this way and I might actually keep it like that.