push pull pot question!

[Deleted]

I have a question about a push pull pot.

I have wired up a bunch of these. But I have a customer that has a guitar with one push pull and no tone control.
I installed a P90 in the bridge and a GFS I think it's called a dream 90 it is like two P90's side by side, it at the neck.

So the problem I am having is the bridge pickup is super tiny sounding. Is there a way I could wire a capacitor, to tame the pick down on it's sharpness with out the need of a tone pot...

E B

[antares]

Sorry EB, there's not enough information about the circuit here. I'd like to have in mind the wiring. Is the push-pull intended to split the Dream 90 coils? If so, it would not have any impact on the bridge pup tone, so I'm confused by the thread title!
Were you thinking of using the push-pull to lift a capacitor soldered across the pup? If you put a capacitor from hot to ground on the bridge pup, it would create a parallel tuned circuit with the pick up winding which would exhibit high impedance at the resultant resonant frequency. Get the value right and it would tame the shrill P90 for sure, but it would have to be a suck it and see enterprise to hit on a suitable value. You'd need a fairly low value capacitor, lower than a tone pot cap.
Would it help to try a 250K volume pot if the present one is a larger value one? That would affect both pups though.
You could try a metal cover for the P90 and ground it. That would calm it down a little. You can buy them on eBay, but watch out for pole piece spacing, P90 bridge pick ups are different from neck pups in their spacing.
If the pup cavity is not screened, some grounded self adhesive copper foil tape would add some capacity to the bridge pup rout which might help a bit.
Or a cheap (maybe even curly) guitar cable / cord, but that would affect both pups too.
At this point I'm going to turn it over to those better qualified than myself!

[dnic]

What does the push/pull control? Is it a coil split or is it volume in one position and tone in the other? Does it still have a 3 way selector switch?

[Deleted]

Right now I have it wired were the neck pickup is split. The bridge pickup is wired to the pot of the push pull. In other words the bridge is wired like a regular pickup on the pot.

All I am wanting to do is to take out some of the harsh bite in the bridge pickup, without adding a tone pot.

I did find a wiring set up for a single push pull. They took the two center lugs and put two caps on, wired together. That's two caps on each of the center lug. Both sides have a two different values to them. Looks kind of like a treble bleed to me but on both sides of the center lugs of the push pull.

I was thinking of putting in a small tone pot and putting it were the pot would make the bridge pickup soften up. Then placing the pot in the control cavity. (because the customer don't want it to be seen) But I am afraid of the tone pot changing the sound of the the neck pickup.

About a week ago I did see where someone added some kind of a cap on a single push pule volume. But like a knuckle head I didn't save it. LOL!

I can try and get a picture up of what I have, later on. But today is a busy day for me.

EB

[dnic]

I think if we look at what a tone pot does we could figure this out. So it bleeds some signal to ground which seems to affect or lower the treble side of things. So if we ground only the bridge pickup through a cap that should reduce some spikey tone. The question is what size will get you where you want to be. Hang some test leads out and experiment with different values till you get what you like. I could be totally wrong but that's how I would go about the process to see what happens.

I think you would need to leave the push/pull out of the equation unless you wanted this tone thing to be an on off type of thing but if that's the case you need a separate switch for that leaving the existing p/p for the coil split.

[dnic]

Should be interesting to see what cap you end up with

[Deleted]

OK... I had the owner of the guitar come by to check out the sound of the guitar after rewiring it. I rewired it to the specks in my book for building guitars.

So any way, I the new over love's the sound of it, just the way it is. So I'll be putting it back together and sending the guitar on it's way. The Owner wants to try playing it in a live setting. So we will see if he (owner) wants any other changes to it.

If you can look at a push pull pot... on the top part of the pot is like 6 lugs... The book shows to ground both center lugs, then use the two top ones for your pickup or pickups for splitting.

So with this guitar having a double P90 in at the neck and a single P90 at the bridge. I split the neck and wired the bridge on the 3 lugs of the pot itself. Center lug being hot, one to ground, the other for the pickup.

Worked out pretty good. It now a good volume all the from low, medium, or all the way up. I was having a bad problem with a lot of volume drop from one pick up to the other. The way I wired this up the first time was from SD. The pickups sounded week and thin and over the top ear hurting highs. The other problem I was having was the volume was on (all the way up) or it was off, or almost off. There was no real volume control.

Now the guitar sound has a fullness to it, that it did not have before. The owner was really happy with the new sound.

Well, this was a first for me. I did not know that wiring it up different would change the sound of the guitar that much. But this one did. So now I'll go to my book. It has a lot of ways to wire up guitars I have not even tried yet. LOL!
EB