Gibson LP 4 core problems

[beldin42]

Hello all. Have just installed a 4 core LP pick up in my LP copy. Thing is, it only wants to work out of phase (red+braid to earth). When I wire it 'correctly' with black+braid to earth I am met with silence!! Any help gratefully accepted.

[D2o]

Apr 28, 2008 5:21:38 GMT -5 beldin42 said:

Hello all. Have just installed a 4 core LP pick up in my LP copy. Thing is, it only wants to work out of phase (red+braid to earth). When I wire it 'correctly' with black+braid to earth I am met with silence!! Any help gratefully accepted.

Hi Beldin42, and welcome to the Nuthouse!

Even though it sounds like it is, I don't want to assume this is a Gibson pickup.

Is it a Gibson LP pickup in your LP copy, or is it an LP pickup copy in your LP copy?

I ask because not all wiring is the same - here is a link that may help you determine if you've got the colors right:

www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=color_codes

By the way, what are you doing with the other wires?

Let us know more of the details if you can.

[beldin42]

Hi and thanks for the prompt reply. Sorry, I should have been clearer, but here goes!

The guitar is a LP copy and is quite nice but the electronics were duff! I have installed a LP pickp in the neck pos and it is a standard single core and braid. The problem pickup is a LP pickup too but is four conductor. Red, black, green, white and braid. I have soldered the green and white together and insulated. As far as I could make out, it ought to be red to 'hot' and black+braid to ground. Using this option, the neck pickup works fine but the multi core bridge is completell silent. However, if I wire black to 'hot' and combine the red and braid to ground, the neck pickup still works fine but the bridge pickup is now out of phase. Driving me mad, but I'm keen to try anything else at all to get this to work.

By the ay, the pickups go to the pots first, not the switch.

Thanks again.

[D2o]

Apr 30, 2008 5:35:00 GMT -5 beldin42 said:

Hi and thanks for the prompt reply. Sorry, I should have been clearer, but here goes!

The guitar is a LP copy and is quite nice but the electronics were duff! I have installed a LP pickp in the neck pos and it is a standard single core and braid. The problem pickup is a LP pickup too but is four conductor. Red, black, green, white and braid. I have soldered the green and white together and insulated. As far as I could make out, it ought to be red to 'hot' and black+braid to ground. Using this option, the neck pickup works fine but the multi core bridge is completell silent. However, if I wire black to 'hot' and combine the red and braid to ground, the neck pickup still works fine but the bridge pickup is now out of phase. Driving me mad, but I'm keen to try anything else at all to get this to work.

By the ay, the pickups go to the pots first, not the switch.

Thanks again.

What you have described as the correct way sounds like the correct way ...

I have modified a SeymourDuncan schematic to "Gibsonize" it - this assumes that the SeymourDuncan site has their Gibson colors correct.

Have a look and see if maybe you've missed something? (for the 2 wire pup, it would just be hot to wiper and ground to the back of the pot)



THIS IS NOT A SEYMOUR DUNCAN AUTHORIZED SCHEMATIC. MY APOLOGIES TO SEYMOUR DUNCAN FOR MODIFYING YOUR SCHEMATIC.

IF IT IS A PROBLEM, PLEASE NOTIFY THE ADMINISTRATOR OF THIS SITE WHO WILL DIRECT ME TO REMOVE IT IMMEDIATELY.

Thank you.

[ChrisK]

Ok, here we go!

You have a pickup that either has some differences or internal connections that you are unaware of, or some "differences" were introduced while you switched the wiring.

First things first. Get out your digital multi-meter. If you don't have one, go get your digital multi-meter.

Measure the resistance of every one of the four wires and the shield to every other wire and shield and write it down.

This will give you the wire pairs for each coil as well as any possible internal connection (or short) of any of these to the shield or other wires. A typical coil will be around 5 to 10 K, but may be higher or lower. Start with the 20 K range.

Write down ALL readings, there will be none that are "nothing".

Change the range to verify all readings on the highest range without going overrange (we call this the search for meaningful/maximum resolution).

Some will be open circuit or overrange, record these as "OR". Make sure that they ARE overrange, and not just beyond the scale that you're using. Verify true overrange/open circuit on the highest resistance scale. Record the range of that scale.

Some will be zero or just low. Change the range to verify these readings on the lowest range without going overrange.


If two wires (and only two) are connected together, you can leave these connected. Make note of this.

_______Red____Green____Black____White____Shield

Red

Green

Black

White

Shield


Once we have this info, it will be easy to see if there are any issues within.

If not, then we can work without.


Do this for all components that you use in guitars. Recording this info for the future helps greatly when thing go awry later on.

[beldin42]

Thanks all. A forum that really works

I think that I will connect this maverick pickup directly to a jack socket, bypassing all the original wiring (which is quite cramped and uses mini pots) and that ought to tell me if the pckup is working or not..........I hope.

It isn't a new pickup tho, it came from an early 90's Les Paul so mebbe it just don't work. Anyway thanks again and I will post the results of my work.

regards