Wiring help: Behind the Bridge humbucker with on/off mini toggle - Volume Drop in when activated

[KevMakesThings]

Hey everybody! So I was reading this thread and got inspired to wire up a GFS thin jazz humbucker behind the bridge of my CV 60s Jazzmaster. It sounds great so far; amplified overtones for some really lush chords and the occasional sonic spikes with direct picking.

The only issue is there's a noticeable volume drop among the rest of the pickups when the humbucker is activated. This happens in both the lead and rhythm circults.

I'm using an SPDT mini toggle and wired the output directly to the output jack. The rest of the wiring is stock. Here is a diagram of how it is wired:



Is there a way to circumvent the volume drop in the current wiring setup? Thanks in advance for any advice!

[Steadyriot.]

Have you tried reversing the polarity?

[KevMakesThings]

Yeah, I've tried flipping the leads and other wiring combinations, either ended up with the same results or effectively became a killswitch.

For reference, this GFS Humbucker has 4 conductors. All workable combos involved Red, Black & Copper. The White wire would usually just cut the signal.
Red = Signal +
White = Coil Tap
Black = Ground
Copper =Pickup Shield Ground

I wonder if the SPDT switch is just not the right tool for this job, and if going with a DPDT would allow for the right wiring combinations. I also considered wiring it to its own volume pot and keep it loaded just in the lead circuit, but I do want to solve this issue first whatever it may be.

[jorri]

Parallel is not often understood. Came into some issues of using a strangle on the bridge pickup myself, which when in parallel turned into a high-pass instead of a low pass.

The signal is bled through the other pickup, the resistance is cut between them as per parallel resistor rule (so if they are the same, then half) etc.
Long and short of it, your signal is AVERAGED in parallel, so are you getting this because an average of sounds with little in common, especially when strings output less volume BTB then would this be a reason for a reduction? If you want to ADD then try series, right?

[jorri]

or i should correct that being the wrong way around: the strangle (high-pass) became a low pass filter like a tone knob being rolled off, because the neck bled through the cap to ground that was on the bridge-only path, so it was like having the tone knob in zero, but at 50% blend because the bridge isn't doing it (its kinda cool i kept it).

[KevMakesThings]

Yeah, through the many trial & errors I found some really cool effects! One version had a lo-fi radio + sitar quality whenever the volume was turned down. Another version ended up being out of phase, fun for a few sounds but ultimately not what I needed.

Below is the updated wiring diagram: The standard Jazzmaster wiring remains intact (Lead & Rhythm circuits functional), and the DPDT mini toggle activates the BTBP which is in series with the Bridge pickup. Only functional in the lead circuit, and controllable with the Volume & Tone controls. Thanks everyone!