EB-3 wiring

[bobyoung]

Gibsonbass.com seems to be down at least right now. I'm looking for a schematic for the wiring, what I want to do is have the full output of the neck pickup along with the bridge in pos #3. I haven't really looked at the wiring very much and understand that there's a choke probably in series with the neck to cut out the treble and maybe a cap in series with the neck for the baritone position #4? Can these be bypassed and be reversed? Has anyone ever gotten full output of both pickups together probably in pos. #3 and if so how did it sound? I realize the neck will probably completely drown out the neck but can a good balanced sound be achieved with the volume controls? I'm just guessing at the wiring so all info anyone has will be appreciated.

[ramone57]

I can't find the schematic I have but did find a wiring diagram, if that helps.  hopefully gibsonbass.com will be back up soon.

[eb2]

I will add a thanks for that, as I am great with diagrams and terrible with schematics.

[doombass]

I have'nt made any mods on my '69 EB-3 but I've been tempted for a while. It's tricky to leave out the choke in position 3 and still have it in position 4. What is also tricky is that the resistor is connected always in series from the neck output.An easy way to try without a choke (make the neck pickup equal to an EB-0) is to disconnect the choke coil wire at lug 8 and the capacitor wire at lug 7. Also use a wire and shortcut the resistor. This way you can see if you like the unchoked sound in position 3. I'm not sure the bridge pickup will be that much drowned out because since the pickups are wired in parallell the high DC resistance of the Mudbucker will be slightly "shortcut" by the bridge pickup.

Also notice that if you want to individually adjust the volumes you must switch the connections on the volume pots. Gibson connected them so both volumes act as mastervolumes. They did for some really strange reason (which is beyond me) connect the output jack side to the mid lug of the pots.

If you can make anything out of it I made an alternative schematics from the original.

Original:



Mod:



Position 1: Full Mud
Position 2: Full Mud + bridge pup
Positon 3: Mud with resistor and capacitor + bridge pup
Position 4: Like position 3 on the original schematics

I have'nt switched the wires on the volume controls on the schematics but I would do that as well.

[ramone57]

I will add a thanks for that, as I am great with diagrams and terrible with schematics.

welcome to the club!   

[bobyoung]

I have'nt made any mods on my '69 EB-3 but I've been tempted for a while. It's tricky to leave out the choke in position 3 and still have it in position 4. What is also tricky is that the resistor is connected always in series from the neck output.An easy way to try without a choke (make the neck pickup equal to an EB-0) is to disconnect the choke coil wire at lug 8 and the capacitor wire at lug 7. Also use a wire and shortcut the resistor. This way you can see if you like the unchoked sound in position 3. I'm not sure the bridge pickup will be that much drowned out because since the pickups are wired in parallell the high DC resistance of the Mudbucker will be slightly "shortcut" by the bridge pickup.

Also notice that if you want to individually adjust the volumes you must switch the connections on the volume pots. Gibson connected them so both volumes act as mastervolumes. They did for some really strange reason (which is beyond me) connect the output jack side to the mid lug of the pots.

If you can make anything out of it I made an alternative schematics from the original.

Original:



Mod:



Position 1: Full Mud
Position 2: Full Mud + bridge pup
Positon 3: Mud with resistor and capacitor + bridge pup
Position 4: Like position 3 on the original schematics

I have'nt switched the wires on the volume controls on the schematics but I would do that as well.

Well if you haven't done it yet, I may be the guinea pig, both look like great ideas and I'm going to attempt them this weekend (I hope). I'll let you all know how this works and sounds as soon as I'm done. It's really cramped in there though and these simple little mods may take me a while.

[doombass]

Looking forward to see what your your verdict is whenever you get around trying it out Bob.

[barend]

I have the tone choke out of the electronic circuit.

This way the neckpickup (position 1) solo sounds much more muddy and there is much more bass in the sound. But it is also very muffled. I never use it solo because of this. But If you use it in combination with the bridge pickup (position 2) it is a better sound than with the tonechoke. But I liked the neck pickup solo with the tonechoke better.

Also with the tone choke removed the neck pickup is much louder than the bridge pickup.

As I said I never use the neck pickup solo but always in combination with the bridge pickup. I have the bridge pickup volume at 9 and the neck pickup volume at 10. Because in position 2 there is otherwise not much difference with position 3 (bridge pickup solo). You can add more bass in your sound with rolling off the volume of the bridge pickup. 

I would like to have the choice between the fully unchoked and choked neck pickup both in combination with the bridge pickup. But I don't think that is possible.

[Dave W]

This is why I like one-pickup basses. Nothing to get confused about. 

[eb2]

Lets be honest - The EB3 is really a one pickup bass with some crap on it.

[barend]

EB2

are you refering to the bridge or neck pickup?, because I prefer the bridge pickup mixed with half of the neck pickup. This way I get the Jack Bruce type of sound. The neck pickup solo is useless for me...too muffled and muddy.

[doombass]

I have a feeling the two of you are on different sides here.

[barend]

There is no way you get the Jack Bruce or Andy Fraser tone with only the neck pickup. And that is the sound most of us want hear from an EB3, isn't it? You have to use full bridge pickup (together with some of the neck pickup) for the clear sound otherwise it will be too muddy. If you want mud than it is ok of course.

[eb2]

Well, yeah, I guess different sides.  javascript:void(0);

I tend to want to get the Zombies sound from my EB3, with Andy Fraser coming in second.  If I got the Jack Bruce tone I would drive a set of Ernie Ball Tubies through my ears!

[Dave W]

There is no way you get the Jack Bruce or Andy Frasier tone with only the neck pickup. And that is the sound most of us want hear from an EB3, isn't it? You have to use full bridge pickup (together with some of the neck pickup) for the clear sound otherwise it will be too muddy. If you want mud than it is ok of course.

I don't know whether or not that's the sound most EB3 owners want. I've never owned an EB3. I admire Jack Bruce as a player but I've never sought to duplicate his tone.

Free was never anywhere near as well known here as on your side of the Atlantic. I would be very surprised if there were anywhere near as many bassists here who are familiar with Andy Fraser.