Gibson - an enigma (1974 EB-3 content)

[Andyjr1515]

You know how 1950's American cars are often so extreme, break so many design and aesthetics rules, are often so darn ugly, that they become utterly beautiful?

 

Well, I often feel the same about Gibson design and manufacture.  It is often so, so wrong - on so many levels - that I can only stand back in absolute admiration.

 

And when it comes to guitar and bass design, there are actually not many 'fixed' rules to break.  Those elements that are, are generally linked to basic geometry, practicality and strength.  Most of the other stuff is entirely down to the whim of the designer or builder and long may it be so.  But ignore the basics and there are going to be difficulties challenges.

 

But let's change the subject.  Let's park all of that and talk about this little beauty - a friend's original had-it-from-new & gigged-for-decades & then-put-in-a-cupboard-for-more-decades 1974 Gibson EB-3, in the 'proper' colour:

 

 

Should he get it refinished, he asked me, what with all the dents and scratches?   "NNNNNNNOOOOOOOOOOOO!!!!!!!!!!!  Absolutely NOT!"

 

Could it be made to play OK again and the electrics sorted out?  "Yes - almost certainly."

 

And could I do something about the bridge...and the fact that the silks go over the saddles?  "Ah...Gibson.   What are they like, the little rascals?  Don't you just love 'em?    Challenging but probably!"

 

And the other stuff?  "Well...it looks broadly OK...hmmm...except...oh...hmmm... that's a bit odd... and, what's that doing there....and...OH....WHAT THE ???? "

 

And so begins another exploration into the wonder of just how much you can break the rules, fix things by breaking other things and take the hardest way possible of solving a very straightforward problem...and still come out by being one of two or three makers in the world that many of us would sell our hind teeth for.   

 

It's genius.  There's no other word for it.  Genius!   

 

 

 

[LouieM]

Kind of off-topic but I love the old EB-3s that have the mudbucker closer to the bridge than the regular ones, they just seem to sound better but are stupidly expensive.
If only someone made a copy of it with the same pickup placement 🤔

[Andyjr1515]

14 hours ago, LouieM said:

Kind of off-topic but I love the old EB-3s that have the mudbucker closer to the bridge than the regular ones, they just seem to sound better but are stupidly expensive.
If only someone made a copy of it with the same pickup placement 🤔

I'm pleased you raised this - because it then made me wonder when that change was made.  It turns out it was in 1972 according to www.flyguitars excellent timeline summary.  And linked to that summary was a Series 2 circuit diagram that matches the switching system on this one!    And as a few solder joints have failed...leaving the tone choke coil rattling around the control chamber...it is very helpful to actually have the correct circuit diagram to work from. Many thanks!

 

I love working on old classics and this one is an icon.  Eccentric, but iconic all the same

 

[thodrik]

I have one of these basses from the exact same year. Same finish. Essentially the same condition except that I still have the pickup covers. I have had it since 2001.

In terms of the bridge, the best thing you can do is get a Babicz full contact replacement. It technically 'devalues' the bass because it is not original, but as it is a drop replacement you can always put the original bridge back on if you  sell it. The Babicz bridge cured the two things I utterly hated about the Gibson three point design: (i) the string silks going over the saddle and causing intonation problems; and (ii) the inability to set the action per string, as the three point tilt bridge is a horrible balancing act. 

The tone and volume controls on mine act more like 'on/off' switches than tapering circuits. There is also very minimal tonal variety as the mudbucker is dominant in both of the two pickup settings. 

Still, it looks cool, which is the key point. 

Edited June 14, 2022 by thodrik

[Andyjr1515]

And so...the notorious 3 point bridge.

 

Very, very nice idea and, with a very small tweak they could be made to work really well.  But the design is flawed and yet they still make them and sell them.  So what's the problem?  

 

It's simply that the distance between the string ball joint clasps and the saddles is too short.  Much too short. 

Result - the string ball joint windings and/or silks go over the saddles.

This is all set at scale length, so in reality, the D, A & E need to be at least 2-4mm further back than this:

 

Ignore the kink in the direction of the strings, I'll come back to that.

 

And most EB-3 owners (and that's most since the mid 70's) have this problem.

 

Can you leave it?  Well yes.  But it means one of the key impacts of tone (orders of magnitude greater than neck wood, fretboard wood, body 'tonewood') - the contact between the string and nut and between the string and bridge - is compromised.

 

There are a couple of solutions:

- cut back the silks and put up with the fact that the string at that far end is often different to the rest of it because of the reverse wind from the ball joint

 

- fit or make an extender

 

Ref the latter, there is a guy in USA who makes and sells what is basically a steel bar with the four string holes that hooks under the clasps and moves the ball ends back 10-12mm.  It works, but is quite expensive with the US shipping and adds more weight to what is already a fairly heft bass.

 

So - what about making an extender out of a hardwood, such as ebony.  And that's what I've done.  I'll cover it in the next post.

 

[Andyjr1515]

32 minutes ago, thodrik said:

I have one of these basses from the exact same year. Same finish. Essentially the same condition except that I still have the pickup covers. I have had it since 2001.

Brill!   In a couple of posts time, I have a question for you

 

[3below]

I encountered exactly the same problem with my SG bass (same bridge design defect all these years later).  I made a 10mm (from memory) aluminium rod spacer.  I seem to remember needing to take care with the ball ends and body contact due to the extension back, hole angles and height.  It worked perfectly well.  Bass now has a Hipshot which is just fine.

Edited June 14, 2022 by 3below

[Andyjr1515]

So - extender.  I found a piece of ebony offcut and cut it to the right depth, but 5mm longer than the extension distance I was planning for.  I then filed an angle, for reasons I'll come to:

 

Next, on the opposite face, I marked the position of the four strings and spotted them with a 7mm brad-point drill.  Lining up with a square, I tweaked the angled face until a vertical drill would create me the necessary allowance for the break angle of the strings:

 

Then to the little drill-press.  4mm holes for the bass strings, 3mm holes for the treble:

 

A filing off of the angled ramp and a groove chiselled in so that the block would slot into the clasps and lay flat against the back of the bridge:

 

And...to my admittedly great surprise...it works! 

 

 

 

 

Next is investigating those odd kinks in the standard string positioning... 

[3below]

A much improved design over the bar/rod with holes extender, avoids the ball ends contacting the body issue.  The bridge alignment on my SG bass is less than perfect, if I had not fitted a Hipshot (with sufficient lateral adjustment) it would have ended up being a plug and re-position the posts job.  On the plus side the quality of the fretwork is very good, only bettered by the Jon Shuker board I have on a bass he repaired.

[Daz39]

14 minutes ago, Andyjr1515 said:

So - extender.  I found a piece of ebony offcut and cut it to the right depth, but 5mm longer than the extension distance I was planning for.  I then filed an angle, for reasons I'll come to:

 

Next, on the opposite face, I marked the position of the four strings and spotted them with a 7mm brad-point drill.  Lining up with a square, I tweaked the angled face until a vertical drill would create me the necessary allowance for the break angle of the strings:

 

Then to the little drill-press.  4mm holes for the bass strings, 3mm holes for the treble:

 

A filing off of the angled ramp and a groove chiselled in so that the block would slot into the clasps and lay flat against the back of the bridge:

 

And...to my admittedly great surprise...it works! 

 

 

 

 

Next is investigating those odd kinks in the standard string positioning... 

Now that's some advanced bodging. Well thought out!

[Woodinblack]

16 hours ago, Andyjr1515 said:

It's genius.  There's no other word for it.  Genius! 

 

Although it is not one of my favourites, I love that they have that massive pickup right by the neck and a tiny pickup 3mm from the bridge, like, we have these pickups, lets just put them somewhere!

[Andyjr1515]

And so to the next enigma.

 

It is unlikely that this is all down to folks changing stuff but:

 

- if you google images of original mid 1970s EB-3's and you look at the ones that have the bridge guard removed you will see some have metal saddles and some have bone saddles

 

- and the bone saddles are properly made.  The saddle adjuster screw thread is actually cut into the bone (something I've never seen before).  Posh job!

 

- and...er...the string slots in the metal saddles are central.  And all the string slots I can find photos of in the bone saddles are offset...and that makes the strings do slightly odd things at the bridge, because the ball end positions are central.  In fact...it does this:

 

- but...er...wouldn't the strings line up better with the pole pieces if the saddle slots were in the middle?   "Not if the neck isn't glued in straight.  Thunderation - this is 1975!  This is Gibson, godammit!  Do you expect us to send on offset neck out without a rectification?  Offset the saddle slots, problem solved!"   Well, of course, I'm speculating.  But, having spent years in manufacturing management, that was a sentiment expressed by some of my factory managers from time to time.   Shortly before I dispensed with their services...  

 

Anyone know if I'm right on any of this?

- are the bone saddles indeed all offset?

- is there any other reason for doing that?

- @thodrik , the question I referred to above...what are your saddles made of?  And if metal, are the slots in the middle and if bone, are they offset?

 

My speculation is because of this - ignore for the moment the string positions vs the pickup - just look at the string to fretboard sides and string to fretboard dots (which, I can confirm, are in the centre of the fretboard):

 

And what happens if I lift the strings out of their slots and put them in the middle of the saddles.  The G string is now further away from the edge at the upper strings:

 

  When you are building a guitar or bass, one of the basic checks when you are fitting a neck is ensuring that all of the dots are in line up the neck and that the bottom and top strings are equidistant from the edges of the board.  Just sayin' 

 

And don't get me wrong.  I LOVE Gibson guitars and basses.  But it's a bit like when, as a teenager, I was always attracted to the girl who was as mad as a brush...

 

 

 

 

 

 

Edited June 14, 2022 by Andyjr1515

[thodrik]

2 minutes ago, Andyjr1515 said:

- @thodrik , the question I referred to above...what are your saddles made of?  And if metal, are the slots in the middle and if bone, are they offset?

Metal, slots are in the middle, no off setting. 

I wonder if running the strings at an angle was an attempt to lengthen the space between the end point of the bridge and the saddle so as to avoid the string silks running over the saddle? I can see no real benefit otherwise.

[bertbass]

I would suspect that if the slot was not offset, then the amount of material between the screw hole and the string slot would not be enough to stop the saddle from breaking in two.

[Andyjr1515]

7 minutes ago, thodrik said:

Metal, slots are in the middle, no off setting. 

I wonder if running the strings at an angle was an attempt to lengthen the space between the end point of the bridge and the saddle so as to avoid the string silks running over the saddle? I can see no real benefit otherwise.

Great - thanks

 

Well, if that was the reason, then it clearly didn't work all of the silks are over the saddles still in the pic above, even thought 3 of the saddles are between 2mm to 4mm too far forward.

[3below]

It is good to see that the neck/bridge alignment is a 'traditional thing' and has carried on from EB0/3 into the later SG bass.  The alignment issue is the same (though much more extreme) that my bass has.  I can't visualise a solution other than plug and remount the bridge mounting post screws.  This then creates the problem of hiding the affected area (Easy with a Hipshot bridge since it will cover it over). 

 

@bertbass Interesting insightful observation 

Edited June 14, 2022 by 3below

[Andyjr1515]

3 minutes ago, bertbass said:

I would suspect that if the slot was not offset, then the amount of material between the screw hole and the string slot would not be enough to stop the saddle from breaking in two.

 

Again, another good suggestion, but I've just measured it and it is 7mm worth of bone, and that is in compression.  Plenty strong enough.  Also, why fit bone when clearly the bridge is designed for metal as fitted to @thodrik 's ?

[Andyjr1515]

12 minutes ago, 3below said:

It is good to see that the neck/bridge alignment is a 'traditional thing' and has carried on from EB0/3 into the later SG bass.  The alignment issue is the same (though much more extreme) that my bass has

 

Love it!     Just like my teenage heart-throb - mad as a brush!

[3below]

7mm of bone under the string is (probably) more than that under F style and some acoustic bass bridges.  No idea why Gibson would fit bone, I can just imagine the amount of breakages when trying to thread it.   I believe they also had a spell of fitting nylon saddles to the 3 point bridge. 

 

After the correct neck - bridge alignment is achieved, another issue that may crop up is neck pickup alignment.  I ended up rotating mine, with the polepieces further away from the bridge, resulting in a reasonably ok alignment.  No real discernible tone difference to my untrained ears, instant Andy Fraser/Jack Bruce is readily available.

Edited June 14, 2022 by 3below

[Andyjr1515]

1 hour ago, 3below said:

After the correct neck - bridge alignment is achieved, another issue that may crop up is neck pickup alignment.  I ended up rotating mine, with the polepieces further away from the bridge, resulting in a reasonably ok alignment.  No real discernible tone difference to my untrained ears, instant Andy Fraser/Jack Bruce is still on tap.

Yes - and actually, this is why I am pretty sure that this is a neck alignment 'fix' - because with the strings down the middle of the saddles as the metal ones would have been, pretty much everything - including the bridge poles - lines up...except for the distance of the G string from the side of the fretboard progressively up the scale and the centre fret dots progressively down the scale towards the nut

 

This is strings positioned down the middle of the saddles as they would be with the standard metal saddles as fitted to @thodrik's (in the same factory in the same year):

 

Start off by observing:

- The strings are pretty much over all of the poles

- The centre dot at the 19th is pretty much in the middle of the A and D strings

- the centre dot at the 3rd is closer to the A than the D

 

So how do we builders line up the necks?

 

Well, it is easier to envisage what happens when you line up a neck by imagining this is a bolt-on.  Loosen the bolts and the neck would swivel around an axis at 19th fret (think clock minute hand, spindle at the 19th dot and nut at 12 o'clock).  The strings are anchored at the bridge, so if you rotate the neck towards 1 o'clock, then the fretmarker will move to the right relative to the A string.  The right hand corner of the minute hand, below the spindle will rotate the other way...but it is close to the spindle so only a teeny bit.  The strings will angle slightly towards the right, but they are so close to the pickups, that distance would be teeny and they would still be over the poles:

 

And that is broadly how we all do it.

 

But - this is a set neck...that's set.  And the problem is, that to fix it from the other end, you have to move stuff across a lot more to achieve the same effect...and you fix one small issue and create many more more serious ones.

 

 

My suspicion is this...and I'll check a few stock shots of other basses with the bone saddles to see if I'm anywhere near right...that:

- probably in those days, the neck misalignment from time-to-time was much worse than this actual example

- that they had a fix for 'bodies with misaligned necks'.  Which was a box of bridges with alternative set of saddles with an offset.  It would have been that or scrap the body and neck.

- this bass ended up in the 'misaligned neck' pile...even though it is actually relatively marginal

- it gets the alternative bridge

- the outer strings now match better in distance to the fretboard edges.  Nothing else does.

 

Of course, I might be totally wrong

 

 

 

 

Edited June 14, 2022 by Andyjr1515

[Woodinblack]

1 hour ago, Andyjr1515 said:

 

Again, another good suggestion, but I've just measured it and it is 7mm worth of bone, and that is in compression.  Plenty strong enough.  Also, why fit bone when clearly the bridge is designed for metal as fitted to @thodrik 's ?

 

is it definately the original?

[3below]

25 minutes ago, Andyjr1515 said:

....  But - this is a set neck...that's set.  And the problem is, that to fix it from the other end, you have to move stuff across a lot more to achieve the same effect...and you fix one small issue and create many more more serious ones.

 

.....   - that they had a fix for 'bodies with misaligned necks'.  Which was a box of bridges with alternative set of saddles with an offset.  It would have been that or scrap the body and neck.......

 

The very reason why I build with bolt on necks.  It allows me to cover up my lack of skills at your level   The build advantage of through necks in this respect is also obvious.  Quite why they could not build basses accurately within the desired time/cost constraints in that era is a mystery (or cynically because they could get away with it and did not care).  On my 2014 SG bass (surely cnc machined?) it should be an absolute doddle and is really inexcusable.
 

The 'box of bridges' is a classic bodge, reminiscent of British Leyland cars. More time rectifying a car at the end of production than Toyota etc spent building one I seem to remember.

[Andyjr1515]

39 minutes ago, Woodinblack said:

 

is it definately the original?

Yes - pretty certain but can check too.  If this had been the only one, then I would have been sceptical...but that a google images search flags up so many with identical saddles...and all with the same offset...then I'm pretty sure it is.

[Andyjr1515]

Anyway, my conclusion is that I will set this up for Chris with strings straight.  I don't even have to change the saddles - the original grooves are so far off to the right, that the strings will sit straight without having to mess about at all (and if I need to cut some more to fine-tune the action height balance, there's enough room for that too.)

 

But all that will have to wait a bit - domestic and family responsibilities, I am instructed informed, will be taking precedence for much of the coming week 

 

But when I'm locked  allowed back in the cellar, the next task is sorting the electrics...so I am delighted at having found the correct circuit diagram as a result of the above discussion

 

 

[BigRedX]

Will it be possible to measure the inductance value of the choke before re-fitting it? IIRC there is no value marked on the Gibson circuit diagram, just a part number.