Dual Humbucker Wiring Help

[MeYatch]

I recently acquired a Gibson EB3 bass with 2 Dimarzio Model One humbuckers.

I have rewired it according to a traditional Les Paul wiring diagram. Everything seems to work as it should, but it is far too quiet in the middle position.

The neck pickup is too bassy, and the bridge pickup is too trebly. I like the tone of both pickups, but its just way too quiet.

If I switch the lugs on the volume pots in order to gain independent volume control, will that help make the middle position louder?

If not that, is there something else I can do?

obligatory pic:


I had the cream knobs and switch laying around from another project. I have some black stuff on its way.

[orangekick]

If the middle position is too quiet, that usually means that the pickups are out oh phase with each other, as far as I am aware. Try swapping the hot and ground on one of the pickups while leaving the other alone.

[lonewolf]

If the middle position is too quiet, that usually means that the pickups are out oh phase with each other, as far as I am aware. Try swapping the hot and ground on one of the pickups while leaving the other alone.

That's the 1st thing I'd check.

If its wired like a Les Paul, you already have independent volume pots.

Switching the lugs on the volume control will only either give you always on full, make the control work backwards or no change.

If the bridge pickup is too trebly, you might want to try raising the value of the tone capacitor or even adding a small value capacitor across the tone/capacitor combination to ground. You can also use smaller value pots, like 250K or even lower if necessary.

If the neck pickup is too muddy, you might want to try lowering the value of the tone capacitor and/or raising the value of its pots to say 1M or higher if necessary. You can also add a bleed capacitor across the volume pot to allow more treble to pass--this is the only capacitor that buying a high quality cap might make a difference.

You can use cheap ceramics on the tone circuit, allowing you to buy several values and try them out to see what works best. Putting an Orange Drop on a tone circuit is like putting a gold plated muffler on your car.

Note that changing one volume pot to 250k and the other to 1M will probably cause a volume disparity between pickups, so you should try the cheaper capacitor solutions 1st.

[MeYatch]

this is the wiring diagram I followed


This little thing underneath it said that switching the lugs on the volume pot will make it so that I have independent volume control when both pickups are on.



I used 250k pots because that's what I had laying around.

I'm pretty sure its not out of phase, but I did install coil taps, and maybe I somehow did that wrong.

This is the diagram I followed for coil tapping:


On the other pickup I simply reversed the red and the green wires so I'd have the outside coils, instead of both neck coils.

If its out of phase that's why, but I don't really know what I should have done to it.

I have been doing some reading and one possibility is that the volume drop is from loading of the pickups. If that's the case the volume should come back with a slight roll off of one volume, that's not really helping, but I'm not sure if that's because I don't have the independent volume control wiring.

[MeYatch]

switched both pickups so the coil taps are wired the same, no more quiet middle sound.

I also added resisters to the wires between the switch and the pots for good measure, not sure how much difference that makes.

Now I am selecting both neck coils, but at least it works.

[lonewolf]

I also added resisters to the wires between the switch and the pots for good measure, not sure how much difference that makes.

A good measure of what? lol

All that will do is cut your output voltage.

[lonewolf]

Yep, that will cause an out of polarity problem.

When you install the pickups properly, that is with the adjustable pole pieces away from each other, you can use the same color wires for both pickups and get the outside poles as the coil split.

[MeYatch]

I also added resisters to the wires between the switch and the pots for good measure, not sure how much difference that makes.

A good measure of what? lol

All that will do is cut your output voltage.

according to this guy
http://www.guitarnuts.com/wiring/stockgibson.php
it will prevent loading of the circuit when both pickups are selected

[lonewolf]

I also added resisters to the wires between the switch and the pots for good measure, not sure how much difference that makes.

A good measure of what? lol

All that will do is cut your output voltage.

according to this guy
http://www.guitarnuts.com/wiring/stockgibson.php
it will prevent loading of the circuit when both pickups are selected

When you select both pickups in parallel, you end up with a lower impedance, just like when wiring speakers in parallel. The addition of those resistors would raise the impedance up to a higher level closer to like when you have just one pickup on.

I suppose this has a small effect on loading, but the voltage losses from the resistors would have a much more detrimental effect by cutting the output than any load matching you might achieve. Most amp inputs are so high-impedance that the load matching effect is insignificant.

If your pickups are around 10Kohms and up, you don't need to do this.

[orangekick]

There might be a small load on the output when both pickups are selected, but that's occasionally good. That's what most standard Jazz basses sound like. The pickups are louder soloed, but they mix together to make a tone that is a combination of the two pickups, just a hair quieter in volume.