sound difference between 60's and 70's EB3

[barend]

By 'EB-0' mod I mean that I have put the tonechoke out of the circuit of my EB3 (as suggested by some on the other forum). Some say that with the original wiring the tonechoke is still in the circuit even if you use the position with the neckpickup solo (where the tonechoke shouldn't be heard according to the description of the varitoneswitch). So if you remove the tonechoke from the circuit you will hear the neck pickup exactly the same as it would sound on an EB-0. Resulting in more bass on the neck pickup

HOWEVER: I think the neck pickup with the mod has much more bass than the original wiring but it also has a lot less treble and therefore it sounds too muddy and muffled (no definition at all). I am not sure if a real EB-0 sounds like that.
I am also not sure if you lose the middish bark what you were talking about when you do the mod.

Hope anyone can give me the answer. Who has done the EB-0 mod on their EB-3?

[uwe]

Let me repeat this to check whether I really understand: You put the tonechoke out of the circuit of your EB-3 and now varitone pos 1 (mudbucker only) sounds different, ie has more bass, but less treble and mids? That would indeed indicate it was choked, but I'm not sure all EB-3s are wired that way, I always thought the mudbucker in pos 1 is unchoked, unadulterated.

With an EB-2, taking out the choke makes the mudbucker sound much more raw, middish and therefore audible. You even hear a glimps of treble. I guess what they were trying to achieve with choking away mids and what little presence there was initially was a sound emulating a doublebass. Except that a doublebass sound has never been especially audible in amplified music, especially not with the bass amplification and recording technology back then.   

Uwe

[barend]

Let me repeat this to check whether I really understand: You put the tonechoke out of the circuit of your EB-3 and now varitone pos 1 (mudbucker only) sounds different, ie has more bass, but less treble and mids? That would indeed indicate it was choked, but I'm not sure all EB-3s are wired that way, I always thought the mudbucker in pos 1 is unchoked, unadulterated.

Yes, only I am talking about position 4 of the varitoneswitch

This is the way it should be on a stock EB-3:
varitone position 1= neck pickup with choke
varitone position 4= neck pickup unchoked
(on a later 70's EB3 it is the other way around, but I am talking about a '68 one)

now with the mod on my bass varitone pos 1 and 4 sound exactly the same, the sound is that of the old position 1, so very muffled and muddy
That is very strange because the tone choke is out of the circuit. You would expect it to be less muffled(?).

But many people on the other forum said that even with position 4 the tonechoke is still in the circuit (the description of the varitoneswitch says it is unchoked but it not completely unchoked) and the sound is different then an EB-0.
If you remove the tonechoke out of the circuit the sound of the neck pickup solo should be the same as an EB-0.

Now I am a little bit confused about what the tonechoke actualy does.
And I am not sure anymore if my bass is wired correctly for the EB-0 mod.

[chromium]

Not to make this even more confusing, but.......           

Keep in mind that "choked" or "baritone" sound refers to that nasal, devoid-of-bass tone that the EB-2s/Rivolis made famous.  Same goes for the EB-3 - the filtering portion of the circuit is basically identical.

On the series-1 EB-3s, I've seen position one on the varitone referenced to as "tone choked", and that is a bit of a misnomer becuase it in fact isn't the choked sound.  The choked/baritone sound of the mudbucker comes in on positions three and four.  Position one is supposed to be unchoked wide-open sound of the neck pickup, but it is plagued by the same residual filtering effect that the EB-2s suffer from.  The filter remains in the circuit, and in this mode has the side effect of rolling off the high frequencies - creating that thunderous low-hovering-cloud bass tone that lacks high frequency definition.  The circuit is here for reference, and I'm assuming that the left-most throw on the switch as drawn is position one (since it wasn't labeled).

Uwe brought the EB-2 residual filtering issue to everyone's attention back at the 'pit.  Prior to that, I always just assumed that absurd bottom-dwelling boooooommmmmm was in fact the "real" sound of the mudbucker.  What a surprise to hear what was actually hiding in there!  I've also heard folks say they prefer the sound of the EB-0 over the EB-3.  I'm thinking that the reason for this is the fact that the EB-0 does not have any of this choke/residual-filtering business going on.  It inherently has the full-range sound as a result - which you can't get on an EB-3 without rewiring it.

...and just to clarify a bit further:  what I mean by "full-range" is the sound of that neck pickup without the nasal choked sound, and without the residual lowpass filtering effect of position one rolling off the high frequencies.  The full-range sound retains the bass that will level buildings, as Bob put it, but it also contains the upper mids and highs needed to give some bite to the sound.

I rewired my '66 EB-2D to get into the unfiltered mudbucker sound.  I later got a '69 EB-3, and since I tend to run position three a lot on that bass, I just left well enough alone.  I then bought a '69 EB-0, and I use that for the unfiltered mud sound.  In fact, I did some fun wiring mods on that one and made some soundclips so you might be able to hear what an EB-0 sounds like in comparison to your own EB-3.  The clips are in this post.

If you made it to this point - I hope that helped!(?)      Gibson really had some eccentric wiring goin' on in their old basses, eh?

[chromium]

One other thing I should mention...  the solution I've learned to use for dealing with the extreme bass output of position one on an EB-3, an EB-0, an EB-2D in "unchoked" mode, and any mod that opens up the full range output of the mudbucker is to use an EQ to notch out the subsonic frequencies.  I think it was Granny who suggested this, and it has worked very well for me.

I use SVT cabs with 10" drivers and no horns, and without the EQ notch on the ~30Hz frequencies, the speaker excursion was (I think) adversely impacting the rendering of the higher frequencies.  By cutting these sub-lows, the speakers stopped flapping like mad and seem to have a fighting chance now    It worked quite well for me.

Of course, if you have a higher-tech amp rig than I do, or cabs with 15-18s - well that might help too with taming the beast!

[barend]

here is the wiring on my EB3. The guitar tech took the dark green wire from the choke (it is not attached to anything now).
Can someone check if this wiring is resulting indeed in the EB-0 mod. As I said I have the same sound now on varitone pos 1 and 4, so I guess this the unchoked sound? since the green wire isn't attached to anything.
The sounds lacks defintion though, it sounds more like the original sound of the old position 1, and it also sounds much louder than the bridge pickup. I have the feeling that the wiring is not right.

I always thought that on a stock EB-3 (series 1) the muffled sound (varitone 1) is the choked sound and that the sound of position 4 is the unchoked sound. But as Chromium said it is the other way around. What I want is the full bloom EB-0 sound from the neck pickup.

[uwe]

This is interesting and you live and learn:

After reading this thread I tested my slothead EB-0 and my slothead EB-3 again and what I had always thought was the dif between D'Addario rounds on the 0 and TI flats on the 3  transpired at closer listening to be indeed the difference between an unchoked and a choked in highs and mids sound. I did the same thing with my 72/73ish maple neck EB-0 and the same era maple neck EB-3L. There is no such difference there, so assuming the EB-3L is stock wired, they changed the set up in later years.

It seems a logic explanation to me why people like Jack Bruce and Andy Fraser did not use the "allegedly unchoked" mudbucker solo mode on their instruments (I always wondered about that, with their amps at the right settings they could have elicited enough mids and treble from the mudbucker for their middish sounds - it just wouldn't have given them the same brawny sound as on an EB-0.

Who'd have thought!


Uwe

[chromium]

I did the same thing with my 72/73ish maple neck EB-0 and the same era maple neck EB-3L. There is no such difference there, so assuming the EB-3L is stock wired, they changed the set up in later years.

I knew there was a resaon that, despite the fact that EBs are already dominant in my tribe, I still lust for a 70s EB-3!  I always assumed the wiring stayed the same, and the maple construction contributed to the extra clarity/focus (well it probably still does to some degree, but in looking at the wiring - it is indeed different)

The wiring confirms what your ears are telling you.  The choke is most definitely out of the circuit on positions 1-3, and only is applied to the neck pickup on position 4.  The way it is wired prevents that whole "side-effect filtering" thing from happening.

here is the wiring on my EB3. The guitar tech took the dark green wire from the choke (it is not attached to anything now).
Can someone check if this wiring is resulting indeed in the EB-0 mod.

What your tech did was remove the choke from the circuit, and as a result also the filter's path to ground - thereby taking the filter out of the circuit.  This should have resulted in position one still having tons of bass, but with upper mids and highs restored (the side-effect lowpass filtering on the neck pickup is now gone), and position four should not sound as bony as it did before, but rather exactly like position one (the choke effect is now gone too).  There is still a resistor inline on the neck pickup, but I don't believe that will have a marked effect on the tone.  Your position one and four should now sound a lot like the .

What you did is electrically identical to the initial approach I took in modding my EB-2D.  I removed the bridge, and desoldered the ground lead from atop the choke (which is hiding under the bridge of the EB-2D).  I had the wide-open neck pickup sound at that point (no more residual lowpass filter), at the sacrifice of the choked/baritone sound.

[barend]

What your tech did was remove the choke from the circuit, and as a result also the filter's path to ground - thereby taking the filter out of the circuit.  This should have resulted in position one still having tons of bass, but with upper mids and highs restored (the side-effect lowpass filtering on the neck pickup is now gone), and position four should not sound as bony as it did before, but rather exactly like position one (the choke effect is now gone too).  There is still a resistor inline on the neck pickup, but I don't believe that will have a marked effect on the tone.

So the mod is done correctly? I want to be absolutely sure, since I don't know much about electronics.
As you said the sound of pos 1 and 4 is exactly the same. But the sound lacks highs and mid and is not as clear as on your sound clip. Also it is much louder than before. Much louder than the bridge pickup. I am thinking about restoring the original wiring. But I am still not sure.
(BTW that resistor is already removed)

One more question: does the choke in the original wiring effect in any way the bridge pickup? In other words did the mod also change the sound of the bridge pickup or only yhe neck pickup.
I really like the sound of the bridge pickup now and I don't want to spoil that if I change it back to the original wiring.

[chromium]

So the mod is done correctly? I want to be absolutely sure, since I don't know much about electronics.
As you said the sound of pos 1 and 4 is exactly the same. But the sound lacks highs and mid and is not as clear as on your sound clip. Also it is much louder than before. Much louder than the bridge pickup. I am thinking about restoring the original wiring. But I am still not sure.
(BTW that resistor is already removed)

It looks like the mod was done correctly, at least from what I can tell from your pic.  It looks like the tech removed the inductor's (choke's) green wire from the rotary switch, covered it with a piece of heat shrink tubing to insulate the bare wire, and tucked it back in there.

I tried this on my own EB-3 tonight, but instead of cutting the green wire (why do I feel like we are trying to diffuse a bomb ), it was faster and less intrusive for me to remove the black wire from the inductor's grounded enclosure:



That should yield the same end result as the mod on your bass - severing the inductor's path to ground, thereby eliminating any filtering of the neck pickup.


I made a sound clip of the results so you can hear what the difference was on my bass:

       

The clip repeats the same pattern, which was played in the same position (fingerstyle over the neck pickup) and with the same dynamics in each iteration.  I did not normalize the levels between each setting - so watch out for your speakers!  This way you can fully appreciate the volume differences in each mode.

The sounds you hear in the clip are in this order:
1.  Original position 4 - "choked" or "baritone" sound of the neck pickup
2.  Original position 1 - unchoked neck pickup, with residual lowpass filtering effect of the choke circuit rolling off the upper mids and highs
3.  Modified position 4 - neck pickup in full glory.  Note the extra mids and highs
4.  Modified position 1 - ditto

One thing that I noticed when playing the bass thru my amp was that there is a very subtle difference between position 1 and 4 after the mod.  Both had the same frequency response, but position 1 was a bit quieter on my bass - and I think that might be due to that resistor remaining inline with the neck pickup.  Looking back at the schematic, position 4 opens up an alternate path around that resistor.

How does your bass sound in comparison to those sound clips?

[barend]

thanks, that is exactly what I needed to hear!

comparing my bass to your soundclip:
in both positions my bass sounds like the second phrase (so like original position 1, so muffled, loud and not clear at all)

How is that possible? because the choke is out of the circuit. And what can I do?

I really like the sound of the clips 3 and 4 that you have made. I want the neck pickup to sound like that! 

[uwe]

All I can say is that my unleashed 1968 EB-2 sounds like modified position 4 too and that that sound is indeed much louder than either the baritone or the original (teble- and mid-)choked sounds of my EB-2.

And I hear a dif in the example betwwen modified pos 1 and modified pos 4 too, latter is even more unleashed.

[chromium]

How is that possible? because the choke is out of the circuit.

Is it for sure?  Here's your photo, but enhanced a bit:



Refresh my memory again- was the wire that the blue arrow points to totally disconnected from the lug that the green arrow points to?  Can you actually pull that wire free and see that it is no longer connected to anything?  If that wire isn't hooked up, I would think the mod would work fine.  We may need to look elsewhere in the circuit.

I'm a bit crosseyed from a days worth of meetings, but I'll catch my second wind here in a little while and have another look at the rest of your wiring.  Its hard to see everything that is going on in there, but it looked normal/original on my first pass - with exception of that extra resistor going to the center lug of the bridge pickup's volume pot.  That's not original, but being that its on the bridge pickup I wasn't thinking it would cause this other mod not to work.  Do you know the history on why that is there?

Here's a pic of my 68/69 EB-3's guts for comparison:

[barend]

Chromium, thanks for finding the time to help me! I really appreciate it.

I have just checked it: the green wire isn't attached to anything. It is loose at the end.

About the resistor (you are talking about the resistor on the red wire right?): the guitar tech put it there (without asking me) because he thought you couldn't hear the difference between pos 2 and 3 of the varitone switch. He put it there to make the bridge pickup softer so there would be a better balance between the pickups. But I told him afterwards to remove it again, so it is not there anymore.

In your post you talked about some residual lowpass filtering of the choke. Is it possible that somehow the filtering is still active? Sounds like it.

[chromium]

About the resistor (you are talking about the resistor on the red wire right?): the guitar tech put it there (without asking me) because he thought you couldn't hear the difference between pos 2 and 3 of the varitone switch. He put it there to make the bridge pickup softer so there would be a better balance between the pickups. But I told him afterwards to remove it again, so it is not there anymore.

Ah -ok.  Yeah that is the one I was talking about - no worries there, then.

I have just checked it: the green wire isn't attached to anything. It is loose at the end.

In your post you talked about some residual lowpass filtering of the choke. Is it possible that somehow the filtering is still active? Sounds like it.

It certainly does sound like it from your description, and comparison to my audio samples.  But I have to admit I'm surprised, and kind of at a loss, what with the choke being disconnected and all.  That really should do it.      

I'll look over your wiring a bit closer and get back to you...