62 Gibson EB0 - 1 humbucker + 1 (dead) JB pickup. What to do?

[Stealth]

Originally Posted by Jim Baritone

Not that I have to do all these things - they're just ideas I've been sketching out to try and get the best use of the available equipment.

I came across an interesting tidbit in Cadfael's guide to bass guitar wiring,

...cut...

Interesting wrinkle in wiring up 2 pickups with 2 stereo pots, since I just happen to have a couple of stereo pots here.....

I got Cadfael's wiring guide, and the wiring you presented was a very early model which had a very basic flaw - there was no isolation between the tone controls. Turning down the tone on one pickup automatically turned down the tone on both of them. Check the next page in the guide for an updated schematic with two isolating resistors.

[Jim Baritone]

Originally Posted by Stealth

I got Cadfael's wiring guide, and the wiring you presented was a very early model which had a very basic flaw - there was no isolation between the tone controls. Turning down the tone on one pickup automatically turned down the tone on both of them. Check the next page in the guide for an updated schematic with two isolating resistors.

Right you are, as usual. I found the updated schematic after making the post, and then dissecting the diagram.

And, since I'm here, yes iiipopes, I know that the early JB's were not "stereo" basses. I was referring to the nickname for two non-concentric pots on a common shaft. Which I just happen to have a couple of because of a stupid mistake I made when I put in an order with my local supplier.

The editorial commentary " for a bass, for most straightforward styles (not needing massive mid cut, compression, etc.), nothing beats the simple J-bass V-V-T controls, whether J-bass, P+J, EB, or any other bass with two pickups. For maximum stability, add a .01 mfd capacitor inline from the hot lead of the bridge pickup to the wiper on the bridge volume pot." has some truth to it, and starting simple is always my rule of thumb.

As I have one original mudbucker, and a 70's added (before I got the bass) J-Bass pickup, I have a mismatch to contend with. There are several possible solutions - obviously I'm going to try the simplest first. The "Flower Power" switch/cap mod for a bass with this combination of pickkups is the simplest and first addition I'm trying on the breadboard.

[iiipopes]

Originally Posted by Jim Baritone

As I have one original mudbucker, and a 70's added (before I got the bass) J-Bass pickup, I have a mismatch to contend with. There are several possible solutions - obviously I'm going to try the simplest first. The "Flower Power" switch/cap mod for a bass with this combination of pickkups is the simplest and first addition I'm trying on the breadboard.

Indeed. It's good to see careful consideration going into what to do with a less than optimal situation as you received it. I'm sure the bass will turn out well however you decide to proceed.

[Jim Baritone]

Originally Posted by iiipopes

Indeed. It's good to see careful consideration going into what to do with a less than optimal situation as you received it. I'm sure the bass will turn out well however you decide to proceed.

Thank you. I'm sure if I worked at it I could add in everything except maybe a steam engine. But if I can keep it simple, with as few additional exterior changes as possible, and still get a good combo of tonal ranges, that would be my preference.

One thing that's a really major constraint is how small the control cavity on the '62 is. I really don't want to do any routing if I can avoid it, or if absolutely necessary as little as possible. It's beginning to look like I'll want to add at least one more switch, to do series/parallel on the neck humbucker. If I use the FlowerPower mod to help even out the two pickups, that will be another added switch, for a total of three with the neck/both/bridge 3-way.

Resorting to small-diameter pots would make a bit of extra room, as would stacked/concentric pots. However, the simpler, the better.

Fortunately, I've received a lot of good suggestions to try out as breadboard rigs before I finalize V.1. Mod.0 and start packing the controls in.

[Jim Baritone]

Well, things have been a bit sidetracked here - a family member had what turned out not to be a stroke, but everything else ground to a halt.

I've been playing with various resistor/pot/cap combinations, all breadboard hardwired as I'm still waiting for my 3-way DP3T toggle switches (On/On/On guitar kind). Certainly an interesting exercise to find combinations where one pickup is not swamped by the other.

I have run into a bit of a puzzler w.r.t. concentric stacked potentiometers. On EBay the only two brands available are CTS and Alpha - neither high-end pots, even the CTS ones in a Fender package. I'd like to find some Bournes, but so far have not located a supplier.

The other issue is the shaft length, or more precisely the threaded portion of the pot which goes through the case and takes the mounting nuts. Both the Alpha "metric" mini-pots and the regular-size CTS pots (stacked concentrics) have a threaded portion approx. 9.5 mm (3/8") long. [pictures below]

This is alright for a J-bass where the pots are mounted to a cover plate, but pretty short for mounting through the wood body on a Gibson EB0.

I'm a bit reluctant to rout the inside of the control cavity much deeper - the wood thickness between it and the top is already pretty thin for strength (it's mahogany - not the strongest wood, and prone to splinter).

So I'm wondering: does anyone know of a source of "long shaft" stacked concentric pots (with a "long" threaded portion), or have thoughts on other possible solutions.

The other next step is to contact Bournes directly to get model numbers, and then try Mouser, etc.

[iiipopes]

CTS pots may not be "high end" from some perspectives, but remember they are an industry standard, would have been original to the instrument, and there are still thousands out there in all kinds of electric guitars and basses that are 10, 20, 30, 40, 50, 60 years old and older doing just fine. They are absolutely reliable.

If you must have stacked pots, the CTS will serve you well.

[P_A_T_esq]

My first post. Lots of great info on here.

I have a newer Epiphone EB-0 that I am in the process of trying my first mods on. I swapped out the 'mudmucker' stock epi pickup for a DiMarzio Model one which made a great difference. I also planned on throwing a Jazz pickup in, but in ignorance purchased a JazzBass bridge pickup and the pole spacing is way off. I was thinking of just installing it on an angle like the routing on the EB0 in this thread. I could return it, but I'll end up eating a bunch of cash on the shipping, tax and brokerage of the pup, so I think I will just try the install. I was going to wire them both with just volume, since I rarely adjust the tone at the guitar anyways.

The epiphone EB0 is cheap, so I'm not worried about botching the job. Seems like a good first mod to try. Any thoughts?

[SGD Lutherie]

Originally Posted by P_A_T_esq

My first post. Lots of great info on here.

I have a newer Epiphone EB-0 that I am in the process of trying my first mods on. I swapped out the 'mudmucker' stock epi pickup for a DiMarzio Model one which made a great difference. I also planned on throwing a Jazz pickup in, but in ignorance purchased a JazzBass bridge pickup and the pole spacing is way off. I was thinking of just installing it on an angle like the routing on the EB0 in this thread. I could return it, but I'll end up eating a bunch of cash on the shipping, tax and brokerage of the pup, so I think I will just try the install. I was going to wire them both with just volume, since I rarely adjust the tone at the guitar anyways.

The epiphone EB0 is cheap, so I'm not worried about botching the job. Seems like a good first mod to try. Any thoughts?

You can get humbucker and mini humbucker sized pickup that would work well as bridge pickups for that bass.

[radrack]

I can't offer advice on what pick ups to use, WAY too subjective.
I have an old Epiphone Rivoli with the chrome cover mudbucker in it. I replaced the pickup itself with a newer Epi mudbucker because they are a lot brighter sounding than the old ones.
Anyway, I am desperately trying to find a plastic cover like yours to purchase, rent or borrow to have a mold made (process will not harm it in any way) so I can reproduce them in very limited quantities. If there is any way to get the cover for a few weeks I will gladly send you some collateral of some sort (blank check, other pick ups, driver lic# etc). Any help would be greatly appreciated, thanks, William Reed(radrack) 503-267-6417

[radrack]

Are you interested in selling the black pick up cover ?
I need one very badly, thanks, Radrack