1987 Charvel Model 4/6 Rewire Issue

[Guitarjunkee]

I have a 1987 Charvel Model 6, and I want to install a new set of Blackouts into this guitar. I want the 3 kill switches to work like stock (turning on and off each pickup). There are 3 knobs, one for active boost, volume, and tone. I want to change each knob to be a separate volume for each of the 3 pickups. I want the guitar to look original so I'm using the stock SPDT Mini Toggle Flat Lever Switches. I feel like I've done everything possible to make this work, but to no avail. Is there anyone that knows how to correctly wire this configuration?

Guitarjunkee

 

[gregory]

Re: 1987 Charvel Model 4/6 Rewire Issue

What about it didn't work?

 

[Guitarjunkee]

Re: 1987 Charvel Model 4/6 Rewire Issue

I was able to get the pots to control the volume on each pickup but the kill switches didn't kill each pickup separately. Each switch killed all the pickups, and vice versa. Then I ran into the problem where all 3 pickups were on and using any one of the pots or switches would shut all the pickups down, nothing worked individually. I was able to get one pickup to work properly but when I tried to wire the other 2 is when the problems began. A wiring diagram would be great.

 

[gregory]

Re: 1987 Charvel Model 4/6 Rewire Issue

Wire each pickup, pot and switch like so:

 

[Guitarjunkee]

Re: 1987 Charvel Model 4/6 Rewire Issue

The first time I wired the guitar was the way you show in the diagram and it's not 100% correct, but it's the closest. The volume pots don't tapper, and when switched to one pickup the other volume pots need to be off or there is bleed from the other 2 pickups. There has to be another way to wire this and for everything to work the way it should. Thank you for your help and if I find the solution I will send you the diagram.

Guitarjunkee

 

[gregory]

Re: 1987 Charvel Model 4/6 Rewire Issue

Shy of putting resistors in series with each pickup (EDIT: which I have now included and should be done to prevent shorting of the pickups' output buffers; thanks ArtieToo), that's the best you can do with passive circuitry. Be happy you are using active pickups or it would have been worse since the loading of passive pickups robs them of their tone.

You will have to feed all the pickups into a summing amplifier in order to ultimately achieve what you want.

FWIW, the type of connection I showed is called independent wiring and I am not a fan of it.

 

[gregory]

Re: 1987 Charvel Model 4/6 Rewire Issue

I re-read your post. There will not be any bleed by any of the pickups that have their respective volume controls at minimum with their respective switches engaged. If they are then the controls are not receiving a proper connection to ground.

Just to make sure, "Output" in my diagram connects to the jack.

 

[Artie]

Re: 1987 Charvel Model 4/6 Rewire Issue

Wire each pickup, pot and switch like so:

View attachment 85997

A potential problem with wiring active pups like that is that when the pot is on zero, you are grounding the active output. If the pup doesn't have a built-in internal series resistor, the smoke may leak out of the cover.

 

[gregory]

Re: 1987 Charvel Model 4/6 Rewire Issue

If too much heat is generated that cannot be dissipated then the result would be a dead pickup. I would hope the buffer in the pickup wasn't deigned so poorly that a shorted output would result in failure, let alone smoke. How many milliamperes do these things draw, anyway? Alas, I suppose I should have figured it out myself before making the suggestion.

The series resistance that I suggested earlier will prevent that type of failure, but (IMO) the whole passive mixing thing is a bad idea to begin with.

I've edited my diagram to rectify the problem.

 

[Guitarjunkee]

Re: 1987 Charvel Model 4/6 Rewire Issue

I'm going to assume that the original preamp booster that was in that guitar had some kind of summing amplifier built into it? what I'm trying to achieve is somewhat similar but with active pickups. The reason I'm trying to change out the pickups is because original pickups in boost mode were too thin sounding for me and when in passive mode they were really thin. Ok for 80s sound, not so good for todays metal. If I put a resister in line on each pickup won't that thin the Blackouts a bit? I researched summing amplifier on the internet and its a bit over my head. Is there somewhere I can buy a summing amplifier or pay someone to make one to my specifications?

BTW, The pickups that have their respective volume controls at maximum with their respective switches disengaged bleed. I'm not able to just switch pickups. I have to turn the volumes off on the pickups that are switched off to not get any bleed from the other pickups.