Reflex/25th - Mod for Bridge Volume

[Ric4001]

I have a 25th Anniversary bass and I miss the ability to change the balance of pickups like some of my other basses have. I'm thinking of changing the passive tone knob into a volume knob for the bridge so I can blend in a little of the bridge pickup with whatever other pickups I have active. I usually prefer the sound of the neck pickup and would love to blend in just a little of the bridge with that. Anyone tried this or have any thoughts on why this might not work as I envision?

[strummer]

Well, if the electronics in your bass is anything like in the Bongo, I'd say it's not an easy operation.

[keko]

I think that's possible, but You must consult nearest electronic engineer, or better electronic technician, to make that tuning in a right way!

It's not that easy, but it's possible, but only in active mode, well, I suppose so, ...must think over!

[Ric4001]

Thanks. I just looked in the control cavity and didn't realize the pots were connected directly to circuit boards. I've been modding my guitars for years, and this is the first one I've seen with that. It will definitely not be an easy mod. Even swapping out a bad pot is a major operation.

[MudvilleStomper]

That's a great idea. I think I'd rather go stack knob on the volume instead of losing the passive tone.

[laneline]

I get the blend function having a Bongo but I'm surprised even if it can be done, you would give up the passive tones, which to me rival any passive only basses.

[Ric4001]

Looking at the schematic, I think it might be easy. I would solder a jumper wire across the two connections for the tone capacitor, which basically provides a path around the tone cap. That turns the passive tone knob into a volume control since, as you turn the knob down it sends more and more of the signal to ground (without the mod, it's sending only the high frequency signals to ground via the cap). Then I solder jumper wires from each of the neck and middle switch outputs to the output lug of the tone knob, which causes them to bypass that tone knob while in passive mode. So then the tone knob is working as a volume knob, but only for the bridge pickup because the other two pickups bypass it. If this works, it's also easily reversible as I can just remove the jumper wires.

Have to think it through more, but i think that works.