Need help with wiring plz!

[boxemall]

Hi folks,
long story short, I was young and made some mistakes lol. But now like 8 years later I’m back, so I dug out my old starter guitar and was wondering why the hell it sounded so horrible and is humming like there is no tomorrow… I’m quite sure I did some fairly dilettantish soldering and the wiring must be way off.
I took a few pictures of my guitar to make it easier to understand what I’m talking about.
It’s got 3 pots. The 1st is a volume, 2nd is a tone and I really don’t remember what the 3rd pot was supposed to be doing. Probably a second Tone? Ah yeah, before I forget, the 3rd pot also has the ability to split the humbucker as it’s a push/pull.

It has 3 kill switches for the pickups instead of a 5-way switch. Back then when I started it was an active guitar and I remember how it bugged the hell out of me when the battery was low. So, I switched to passive SD’s with high output since I was hunting that „ high-gain-shred-the-metal-tone “.
I took a picture oft the pickups' underside but I don’t have any stickers nor original packaging/wiring diagram. I guess it’s been a long time and a couple of moves/years later some stuff just went missing, so I'm hoping there’s a safe way to find out what kind of pickups I got there. All I remember is when I bought them, I picked the humbucker and asked the folks at the shop which single coils would fit the humbucker sound wise. I took what I was told without further ado, … As I already mentioned, I was young and didn’t know much about guitars anyway.

The Plan was to give the guitar an overhaul since it’s getting close to 30 years now. But when I plugged it in it sounded horrible, so I checked the electronics and couldn’t make sense of what I saw,...

I am asking for advice how to make a proper setup with 3 kill switches with what I have at hand. I'm bad at electronics but learned how to solder over the years. As you can see on the pictures at least the copper foil was done properly, at least that’s what I think. Oh my,… it’s really been a long time…
I hope some of you guys can help me identify my pickups but what’s even more important, come up with a nice wiring diagram that I can use.

I hope you don’t mind the watermark on them pictures, I simply forgot to turn that nuisance off, …

Thanks for reading,

Regards!

 

[GuitarDoc]

Re: Need help with wiring plz!

Can't really see your wire connections or trace each wire to see where it's going/coming from. Don't have a clue what your 3rd pot is doing.

But the wiring should be quite simple.
Connect the leads from each pup to the top lugs of their respective switches (black from humbucker and whites from singles).
Connect the middle lugs of the switches together and to the input lug of the vol pot (left lug).
Connect the middle lug of the vol pot to the middle lug of the tone pot and to the hot lug (tip) of the output jack.
Connect the right lug of the vol pot to ground.
Connect the right lug of the tone pot to the cap and the other wire of the cap to ground.
Connect the red and white from the bucker to one of the middle lugs on the p/p. Connect the bottom lug on the same side to ground. This will split the bucker when the p/p is pulled up.
Connect all grounds together and to the ground lug (sleeve) of the output jack.

The 3rd pot is extra but could be used as you want...another vol pot or tone pot for one of the pups, possibly the bucker.

 

[boxemall]

Re: Need help with wiring plz!

Ty for your helpful response and sorry for my late reply. Had a really busy week.

I get your wiring directions, but i have two more questions. How would I connect the humbucker to the 2nd pot in a way that i can use it as a second tone AND still be able to split the HB (remember that the 2nd pot has a push/pull function?). Also I'm not sure if it's visible on the picture that I took, but when you take a close look at the electronics cavity, there's some kind of resistor attached to the 2nd pot. I may have left it there from back when it was still an active setup. Do i need to remove it or maybe replace it even? If so what kind of resistor does it have to be? I'm also wondering if the copper shielding works as ground? Maybe i have faulty solder points and that's why it's humming so bad.

Hope you'll find some time to answer.

Tx in advance,

Regards!

 

[Dave Locher]

Re: Need help with wiring plz!

If the guitar came factory with active pickups there is probably no ground to the bridge. Without that it will always hum like crazy.
The humbucker is a Distortion, I believe. Good for metal.
It looks like the middle pot is a tone control.

That's all the help I can give. A total rewire is your best bet

 

[boxemall]

Re: Need help with wiring plz!

Good point. I think i haven't connected ground to the plate the trem springs are attached to. I'll look into it. And yeah a total rewire was the plan but as i mentioned i kinda fail at electronics. That's why i asked for advice in the 1st place. I still wonder about those log resistors i see so often. Are they necessary? What do they do anyway? I thought a pot alone does the trick?

Regards.

 

[GuitarDoc]

Re: Need help with wiring plz!

Don't know what you mean by "log resistor", you are probably referring to the capacitor attached to the tone pot. The cap is what determines how much of the higher frequencies are removed as you turn the tone pot down. A .010uf cap will remove only the very high frequencies, a .020uf will remove the very highs and some lower highs and upper mids, a .047uf will remove the highs and most mids.

Yes, you could use that third pot for a dedicated tone control for just the humbucker, but that would require different wiring than the "master volume, master tone" wiring I already gave you. It becomes a little tricky because you first have to wire the single coil pups to their switches (top lug) and from each of the top lugs to the right lug of their tone pot (you'll probably want a .047uf cap on that tone pot connected between the middle lug and ground). Then from the switches (middle lug) to the first lug of the master volume pot, and from the middle lug of the vol pot to the jack. Then you wire the hot lead (black) of the bucker to its switch (top lug) and to the third lug of that "extra" pot (leave the wiring of the p/p as is). Wire a cap (start with a .020uf) from the middle lug to the casing of the pot (ground). And from the bucker's switch (middle lug) you also wire to the first lug of the vol pot.

The two single coils will share the same tone pot and the bucker will have its own tone pot and p/p split. All three will share the master volume.

 

[boxemall]

Re: Need help with wiring plz!

I know this is far from complete, but as I'm bad at wiring diagrams I hope you can take a look at what I did so far,...
There is still some missing connections mainly due to me being confused about the P/P pot and its myriad connectors...

And fyi I really want to make the 2nd (split and tone) pot a dedicated tone for the HB.

Regards!

 

[GuitarDoc]

Re: Need help with wiring plz!

Good diagram. But there are a few corrections to be made. Typically when we talk about wiring a guitar we do it as if we are looking into the control cavity...so we are looking at the backs of the pots oriented up. Your diagram is just the opposite, which is ok, but you just have to wire the lugs opposite as well. So the input lug of the vol pot will be the one on the right in your diagram. The left lug should be grounded to the back of the pot.
The wires from the switches to the SC-Tone pot need to go to the left lug.
Remove that wire connecting the vol pot middle lug and the single coil tone pot middle lug. It is redundant for the single coil pups because they are already wired to the tone pot and it would also make the bucker go through both tone pots.
The red+white wires from the bucker should go to either of the middle lugs of the p/p switch (let's choose the left side). Then you'll need a wire from the top (on your diagram) left lug on the p/p to go to ground.
Move the lead wire of the bucker from the right lug (on your diagram) of its tone pot to the left lug.
Put a .022uf cap between the middle lug of the HB-Tone pot and ground, as you did with the SC-Tone.

That should give you what you want.

 

[boxemall]

Re: Need help with wiring plz!

Can I bridge the upper SC lugs together? That way I would only have to use one wire to the pot.
Since white on white doesn't really work, I used dotted gray for the SC and HB wire.
Also, "we're" still missing the green HB wire and the black SC wires. Should those be grounded as well?
If I'm getting this right, I need to bridge all ground-points too, correct?

Q: When I look at the pickups from the front (guitar front, neck north), does the white SC wire have to go left or right?
It seems I had them switched, one wire went left, the other to the right side. Don't know how this happened but back when I first installed them the caps must've fallen off and I put them back on without paying attention.

Sorry if I'm asking too much but I want to get this right the first time I do this.

 

[GuitarDoc]

Re: Need help with wiring plz!

I see several problems:
You don't want the HB-Tone pot lug 1 grounded, but you DO want the p/p grounded to get split. Just remove that wire from lug 1 and put it on lug 4 (on the p/p switch).
Yes the green wire from the bucker, the black wires from the singles, the ground/sleeve of the jack, and the backs of the pots all need to be grounded.
And I just noticed another big problem...both inputs and both outputs of the two SC switches are shorted together so either switch will work both SC pups. I don't know why I didn't see that earlier. Sorry. You will need to disconnect one of the SC pups from the tone pot.

So, with your setup of individual on/off switches instead of the typical 5-way pickup selector switch, you can either have master vol and master tone for all three pups, or you can have master vol with tone for 2 of the pups. Or you could have master vol and tone for the two single coils and only vol and split for the bucker or just tone and split for the bucker.

 

[boxemall]

Re: Need help with wiring plz!

I reworked the diagram according to your suggestions.

Hopefully it's cleaner and easier to read now, as I added some joints where wires "come together" to visualize that they have the same endpoint.
Also, I picked up your hint and turned them pots over, so we're looking at the back side now and flipped the P/P pot as well.

While I was searching for caps, I stumbled over some pots and realized that they come in 250K and 500K versions.
That's a question I never asked, but I wonder if it matters which type I use? I don't know what kind of pots I have atm,...

Do I need to look into it and replace them in case they are the wrong type?

 

[Teleplayer]

Re: Need help with wiring plz!

Generally 250k pots are for single coils and 500k are for humbuckers. When combining both types of pickups some people will compromise and choose a 250k volume control, and 500k tone control. Otherwise where 3 controls are used, it could be 250k Master Volume, 250k Tone control for single coils, and 1Meg tone control for the humbucker. So there are a range of solutions.

If its desired to make it more complex, some people will use a 500k volume control with a fixed load resistor that is switched in when the selector is in the single coil positions. That is intended to simulate the effect of having a 250k volume control applied to the single coil pickups. My suggested diagram using this approach is shown below, but you may be happy with the simpler approach. I also changed the connections so that only one of the tone controls is active at any time.

 

[GuitarDoc]

Re: Need help with wiring plz!

That looks great. You've done a super job on your diagram and it looks very clear. But when you flipped the pots over you changed the lugs on the HB-Tone pot. No big deal, just move the lead from the bucker to lug 3.

That should work

Generally, 500k pots work best with humbuckers and 250k work best with single coils. 250k vol pots reduce some high end, 500k vol pots are brighter. When used as a tone pot the main difference is the taper and ironically has less effect on the tone than when used as a volume pot. Your vol pot is a master so it is used on the singles and the bucker. Whatever value you have, just try it and see how it sounds to you. If the singles sound good but the bucker sounds too dull, you probably have a 250k and you may want to change it to a 500k. There really are no rules for this...it's just what works and sounds best to you. There are even 330k and 1meg pots available. And they come in linear or audio taper just to add to your knowledge (or confusion, which ever the case may be).

But just try what you've got and see how it sounds and let us know what you think.

 

[Teleplayer]

Re: Need help with wiring plz!

If the control pots were originally used with active pickups they may be 25k or 50k. In that case they will need to be changed.

 

[Artie]

Re: Need help with wiring plz!

That is a nice diagram.

 

[Jack_TriPpEr]

Re: Need help with wiring plz!

Generally 250k pots are for single coils and 500k are for humbuckers. When combining both types of pickups some people will compromise and choose a 250k volume control, and 500k tone control. Otherwise where 3 controls are used, it could be 250k Master Volume, 250k Tone control for single coils, and 1Meg tone control for the humbucker. So there are a range of solutions.

If its desired to make it more complex, some people will use a 500k volume control with a fixed load resistor that is switched in when the selector is in the single coil positions. That is intended to simulate the effect of having a 250k volume control applied to the single coil pickups. My suggested diagram using this approach is shown below, but you may be happy with the simpler approach. I also changed the connections so that only one of the tone controls is active at any time.

View attachment 105360

The detail of the components in that diagram is very nice. What software did you use to create this diagram?

 

[boxemall]

Re: Need help with wiring plz!

@Jack_TriPpEr, I used a program called "Inkscape".

It's free and should be easy to find if you hit your favorite search engine. I had to create the pots in the last iteration myself since I couldn't find any that suited me. I wanted to have the "back" view. It's so much easier to know what ppl are talking about when everyone can see it. That was the reason why I put numbers on the P/P. The pots with the shaft looking upwards I found on the webs.
The Jack was an image I found on the web and the pickups were taken from a schematic and resized accordingly.

If you are interested I could mail you everything I have used so you could use it yourself in case you wanted to. You'd just open Inkscape and drag'n'drop them in, draw a couple lines (wires) and that's it. Initially I wanted to upload to this forum but it only takes pictures.

I spend half a day tinkering with a couple tools and settled with Inkscape. I tried "TinyCAD" which prolly would have worked as well, but that is a more professional approach as you have to work with circuitry symbols.
If you're not into electronics like me, it would have taken me another couple hours to find out how the symbols for each and every piece I needed look like.

Overall I think the graphical diagram is much easier to read and create for everyone.

@Teleplayer: If only one of the tone pots would be active at any time which one would be "master" in case I'd be running an SC and the HB together?


I'm busy for the rest of this week but do hope that I'll find some time to start working on it this weekend. I'll keep you posted!


Thank you so much for your help @GuitarDoc and for your suggestion @Teleplayer!


P.S.: @GuitarDoc - confusion ofc! :smash:

 

[Teleplayer]

Re: Need help with wiring plz!

@Teleplayer: If only one of the tone pots would be active at any time which one would be "master" in case I'd be running an SC and the HB together?
P.S.: @GuitarDoc - confusion ofc! :smash:

In my diagram the Tone controls are switched by the toggle switch for the bridge pickup.
1. bridge JB selected: 500k Bridge tone is active
2. bridge JB Not selected: 510k Load resistor and 250k Tone control is selected.

When the JB is selected you get the 500k bridge tone control no matter what other pickups are selected.
To me it seems ok when the humbucker is in full series connection. I'm just thinking whether something better could be done when the coil-split is activated.
Its a matter of what can be done with the switch hardware you are using. If I'm able to think of an alternative scheme I will update the drawing and post it in the next couple of days.

 

[Teleplayer]

Re: Need help with wiring plz!

Updated schematic to add an extra 510k load when the humbucker is split. If 510k makes the split sound too warm, it could be swapped for a 1 Meg resistor or omitted completely.

 

[boxemall]

Re: Need help with wiring plz!

That looks interesting. I was hoping I'd be able to get all parts but one electronics shop was closed and the other didn't have the proper pots so i had to order them.. at least i was able to get them 0.022 caps and the 510k resistors.
I desoldered the old pots but my multimeter says only the 250k pot works the other two including the p/p are broken whatsoever.

That's why i decided to get all new pots. It's just gonna take a few more days?

Regards