EB3 tone choke removal

I want the tone choke of the neck pick up on my EB3 removed. I have brought it to a luthier and he did a mod which can easily be returned to it's original position.

He removed the tone choke condensor (?). So now I have position 1 and 4 is the same: neck pickup unchoked, position 2 is bridge pickup and position 3 is both (unchoked).

Should this be enough? or is there something else which needs to be removed?. because I don't hear much difference with how the sound in position 4 is now and then. In position 1 I hear the difference of course.

Also he added a 22k resistor for the bridge pickup. But now my bridge pickup is too soft. So I what this resistor to be removed. Or maybe a lighter resistor. Any ideas?

so you'll just have neck / bridge / both? Why not go with a 3-way switch?

One thing i've always disliked about the EB3 is that you can't turn the volume of one pickup down and still get volume out of the other, when both are selected.

I'd like to have neck pickup on full, and just dial in maybe 2-3 on the bridge, but with tone on 3 or thereabouts. But you can't, it drops both volumes down.

I don't want to change too much on my bass. I just want the tone choke removed and I am not completely sure if it is removed now.

But you're right it is annoying that you can't control the volumes of both pickups, you can but in a limited way.

Barend- there are usually two wires coming out of the choke.  You could probably look to see if either side is disconnected.  The choke is that big tin enclosure in the middle of the control cavity:







All you would need to do to bypass the choke is to disconnect the connection to ground - highlighted in red in this schematic:






If you still wanted to retain the filtering functionality of the varitone, there are a number of ways to go about it.  I think the least intrusive would be to have one of the original pots replaced with a pot/switch combo (push/pull, etc...) to cut the choke's ground connection at will.  If done with care, the original parts could be put back (if you wanted) in the future, and it would be really hard for someone to detect that anything had been altered (again- if done well).  

(One note about the push/pull pots - be aware that the bodies on these basses are fairly shallow, and some of the pots available with integrated switches might be too tall to fit.  Just something to doublecheck before you buy them)

Hi Chromium, thanks for the help and the pics! that is great.

Here is a picture of how my electronics are right now. I don't know much about electronics so maybe someone can check it from the picture. The luthier told he did something with the green wire.
I don't have the tone choke anymore on position one. But I want to be sure that it is completely removed from the circuit.



and what about the 22k resistor for the brigde pickup. Do you think that is a good idea? I think the bridge pickup sounds too soft now and i think I want it removed.

It looks like he disconnected the green wire from the rotary switch (green arrow), covered the bare wire with a piece of black heat shrink tubing (blue arrow), and tucked it away into the body route that leads off to the neck pickup.  You could probably pull on the wire and see that it is loose, and just sitting in there:




If that's the case, then the choke is out of the circuit.  You should hear quite a difference now, compared to the muffled thunder of the original position one.  Now you are in full-range EB-0 mud territory!  

I'm not sure of what impact removing that resistor will have - I've never tried it.  You could actually just leave the resistor in there and connect a bare wire to both sides of it.  That'll essentially short it out of the circuit, as if it wasn't there.  If you do try that, let us know how it works!

One thing i've always disliked about the EB3 is that you can't turn the volume of one pickup down and still get volume out of the other, when both are selected.

I'd like to have neck pickup on full, and just dial in maybe 2-3 on the bridge, but with tone on 3 or thereabouts. But you can't, it drops both volumes down.

I have no idea why but Gibson decided to connect the wire from the pickup to an outer lug of the volume pots on EB-3's. Usually you connect the mid lug. Instead they reversed it and put the "output wire" on the mid lug which results in the "wrong side" being shortcut to ground.. If you want to you can simply switch places of these wires to get a normal function (ie only the pickup intended to is shortcut to ground) without the volume controls interacting when using both pickups.

It looks like he disconnected the green wire from the rotary switch (green arrow), covered the bare wire with a piece of black heat shrink tubing (blue arrow), and tucked it away into the body route that leads off to the neck pickup.  You could probably pull on the wire and see that it is loose, and just sitting in there

yes, that is what he has done. Now you say it, that is what he told me. But I didn't know if that was the correct way to get the tone choke out

If that's the case, then the choke is out of the circuit.  You should hear quite a difference now, compared to the muffled thunder of the original position one.  Now you are in full-range EB-0 mud territory!  

Of course I hear the diffence with position one (that is now the same as position 4). But frankly I don't hear any difference with position 4. I would have expected that because I read hear on this forum that the tone choke was also in the circuit in position 4.

I'm not sure of what impact removing that resistor will have - I've never tried it.  You could actually just leave the resistor in there and connect a bare wire to both sides of it.  That'll essentially short it out of the circuit, as if it wasn't there.  If you do try that, let us know how it works!

when I brought the bass there was no resistor (it are the original electronics) but he has put a 22K resistor for the bridge pickup (you can see that on the picture). He said the pickups are more balanced this way. But now the bridge pickup is too soft compared to the neck pickup. So I think I want it back to the original state (without the resistor). Or maybe a lighter resistor so the volume drop is less.

But frankly I don't hear any difference with position 4. I would have expected that because I read hear on this forum that the tone choke was also in the circuit in position 4.

Position four on my EB-3 engages the choke and cuts the lows and low-mids from the sound of the soloed mudbucker.  This yields a more clear-and-present mud sound, but it is thinner and lacks the body and fullness (and volume) of the wide open mudbucker (ala the EB-0).  When I have the two side-by-side, the difference is really pronounced.

I suppose if you are curious about it, you could always temporarily clip that green wire back onto that prong from which it was unsoldered and A/B the effect on position 4 - see if it really made a difference on your bass.

Quote from: chromium

If that's the case, then the choke is out of the circuit.  You should hear quite a difference now, compared to the muffled thunder of the original position one.  Now you are in full-range EB-0 mud territory!  

Of course I hear the diffence with position one (that is now the same as position 4). But frankly I don't hear any difference with position 4. I would have expected that because I read hear on this forum that the tone choke was also in the circuit in position 4.

Note (on the schematics) that when in pos 3 and 4 the cap in the choke circuit acts different from when in position 1. In pos 3 and 4 it works in parallell with the resistor but is in series in the signal path making it act like a high pass filter. That's why you don't hear much difference. If you really want full mud (EB-0 way) you'd have to bypass both the remaining resistor and cap.

So doom you are saying that right now I don't have the fully mud (EB-0) sound and the tone choke is still in the circuit of position 3 and 4? even with the green wire disconnected to the rotary switch?
That is something I really want to know and why I started this topic in the first place.

I think position 4 has very much lows, even too many. That's why I always combine it with the bridge pickup

So doom you are saying that right now I don't have the fully mud (EB-0) sound and the tone choke is still in the circuit of position 3 and 4? even with the green wire disconnected to the rotary switch?

Yes, when using position 1 you have a resistor in series in the signal path (just like your bridge signal after the luthier mod). In position 3 and 4 the cap is also engaged in the manner I described earlier.

I think position 4 has very much lows, even too many. That's why I always combine it with the bridge pickup

That's strange because if I'm not totally mistaken it should cut some bass frequensies when using pos 4 even with the coil cut out of circuit. Position 1 is supposed to have more low end than pos 4.

ok, so what did disconnecting the green wire have for effect then? only that I am not able to get the tone choked sound in position 1? that sound was too muddy and useless for me anyway. But if that is the only thing then disconnecting the wire was pointless because I didn't use position  1 and now I also don't use it because it is the same as position 4 now.

I am still a little bit confused.

I am using this bass as my main bass in one my bands so I want it to function as good as it can.

I have no idea why but Gibson decided to connect the wire from the pickup to an outer lug of the volume pots on EB-3's. Usually you connect the mid lug. Instead they reversed it and put the "output wire" on the mid lug which results in the "wrong side" being shortcut to ground.. If you want to you can simply switch places of these wires to get a normal function.

Wow, i'm definately going to try that. Along with Joe's serial/parallel coil tap modification

That could be amazing. An EB3 with greatly increased tonal possibility. I've got three EB3 projects on the go (all at luthiers having neck or body repairs) I reckon i'm going to try these on at least one of them.

ok, so what did disconnecting the green wire have for effect then? only that I am not able to get the tone choked sound in position 1? that sound was too muddy and useless for me anyway. But if that is the only thing then disconnecting the wire was pointless because I didn't use position  1 and now I also don't use it because it is the same as position 4 now.

I am still a little bit confused.

This probably isn't helping with the confusion level, but here it goes anyway  

Doom is right that the resistor is still in the circuit (pos 1) and the resistor and cap and in the circuit in parallel (pos 4, etc..), but what I'm confused about is where they would have an discernable effect on the actual sound.  Since the cap is inline and in parallel with the resistor in pos 4, it should just be passing high frequency signals, and the full range signal is still passing thru the resistor - in other words, nothing is being diverted to ground (filtered out) since the path to ground was broken by removing the green wire.  I can see where these components will have an effect on the overall impedance of the circuit, but not on the actual sound so much.

Doom- please help me understand it if I'm missing something there - I'm far from an expert on this stuff  :shock:    and I'd like to know

Barend- the way it is right now, does your bass sound the same on position 1 and position 4?  That is what I would have expected from the change you made of removing the green wire.  I'd expect pos 1 to now sound less muffled, and pos 4 to now have more low end and low mids - and both positions should sound almost exactly the same.  

BTW- I like that trick with the volume controls too.  I wish I would have known that when I rewired my EB-2D with the choke bybass!