Rewiring rare jazz guitar, still major buzz

[beachwail]

I have a Hofner Vice President, it's a 2-humbucker (2vol, 2tone) beautifully crafted guitar. There's floating pickups and a floating ebony bridge. There is no ground wire attached to the bridge or tailpiece.

I want to change it to 1vol, 1tone and hopefully fix the awful buzzing in the process. This will be my 6th or 7th time rewiring a guitar so I'm not a complete noob...but still very inexperienced

The first red flag is the pickups. The are supposed to be Kent Armstrong designed for Hofner, but markings do not indicate anything other than Hofner. They each have non-standard wire colors as follows:
Yellow & White twisted together
Brown & Bare metal twisted together
Green

I assumed Green was hot and Brown/Bare was ground.

The rewire was modeled afterSeymour Duncan's diagram for 2h, 1v, 1t, 3w. Everything seems to work, yet there is still MAJOR LOUD buzzing. It mostly goes away with both pickups on and my skin touching the input jack.

Any idea what could be wrong? It seems like it has to be a ground issue... ?

Thanks for your time! Mike

[newey]

Beachwail-

Hello and Welcome!

I don't have a quick and easy answer for your problem. It does sound like a grounding issue.

The first red flag is the pickups, they each have wires colored as follows:
Yellow & White twisted together
Brown & Bare metal twisted together
Green

Now, when you say "twisted together", do you mean that the wires are electrically connected by twisting the strands together? Or are they just twisted along their length, as in a twisted pair of wires?

I assumed Green was hot and Brown/Bare was ground

This hypothesis may require some testing. Do you have a multimeter?

If the yellow and white wires are connected together (as opposed to being merely twisted), it's a good guess.

If it's backwards, everything would still operate, but perhaps be noisier.

You should also check the wiring to the output jack to see if perhaps you reversed those leads.

But those are just my off-the-cuff guesses, there may be other issues afoot.

[beachwail]

Quick response, I'm super impressed.. What a cool resource
Thanks for that!

To answer some preliminary questions:

"twisted together" referred to an actual electrical connection.
The Yellow & White were connected and terminated.
The Brown & Bare were soldered together, onto Volume pot.

I do have a multimeter, but it's old and I'm not too handy with it.
My grandpa gave it to me when I was young to test battery voltage. I would certainly buy a new one if it is needed!!

**

I first tested the output jack theory, reversed those 2 and it solved a lot of the buzz. That was likely part of the problem. However, there is still heavy buzz in the 1 and 3 position (with just one pickup active) and it's acceptably quiet in the 2 position (both pickups active). It actually reminds me of the way single coil pickups would behave RWRP, cancelling hum in the middle position....

Again, all of the buzzing scenarios decrease a little bit when I touch my flesh to the input jack.

The buzzes also do not seem to be from electrical interference, as it's still exponentially louder than my single coil Telecaster in my (quiet) studio room.

[newey]

The Yellow & White were connected and terminated.

Terminated to what? Each other?

In a standardly-wired humbucker, the coils are in series, with the "return" of one coil connected to the "send" of the other. Your yellow and white wires make sense connected together, but not connected anywhere else (assuming this is where the 2 coils are wired together).

The bare wire is clearly a ground, properly connected to the vol pot, as is the other return wire, presuming that's what it is. The green thus makes sense as the "send" of the series pair. So, it sounds like you've got the wiring correct.

Is this already all back together, or can you post some pictures of the wiring? And can you post a diagram of what you wired?

It actually reminds me of the way single coil pickups would behave RWRP, cancelling hum in the middle position....

Another thought. Have you checked (screwdriver test) that both coils of each HB are working? If you were missing a coil on one, that would explain your statement above . . .and might explain some noise as well, when that pup was on singly.

[beachwail]

There doesn't appear to be anything wrong with the pickups, although they are covered and sealed so I haven't been able
to check any specifics.

This schematic is what I followed:
www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=2h_1v_1t_3w

I cannot easily take photos right now, but when I take it back apart I will. A fully hollow guitar with no pickup holes is very difficult to maneuver into.

Keep in mind that this is a somewhat rare, german-made guitar, with custom made pickups--- It's very difficult to get customer service or exacting specs from Hofner. Is it possible the pickups might be noisy as stock? the pots might be bad, the wires might be bad? The tone cap? I can go out and buy some wire and start from scratch. This just doesn't add up.

[D2o]

You should test every component when you do get access to it.

It could even be as simple as a poorly soldered joint ...

One of our members, lpdeluxe, had to rewire a holla'body and left an excellent epistle on the steps involved - you should take a look, as there are ideas and tips that may be helpful in your efforts.

See reply #17 in thinbody f-hole wiring.

D2o