Some help with a 1974 Gibson Les Paul Signature (Low impedance pickups)

[stairwaytokevin]

Hello everyone, new guy here and I hope you all have a great New Years! I could use a bit of help please with repairing an old Gibson Les Paul Signature (The 70's thinline ones). Apologies if this is the wrong section in the forum; I had a look through everything and I thought this would be the best place to post.

So, it seems that about 30 years ago someone decided that this guitars original electronics were not what they wanted and changed them to a typical Les Paul style configuration. If you're familiar with these instruments then you'll know that they are equipped with low-impedance pickups and I'd imagine that's why it hasn't worked since. Both the pickups are original, working and read 25-26 ohms so that's good news but unfortunately the rest of the original electronics are long-gone. After looking over the schematic I can tackle the wiring and replace/substitute most parts but I must admit that making the small transformer is beyond me. I'm aware that as a last resort I can still use a little line matching transformer to get sound but it would be nice to actually have the three position 'level control' to change the output impedance as well.

Can anyone make something like this or point me towards someone who can please? I've given up on finding the original part (number: 70-478) its like looking for hen's teeth. Epiphone did a re-issue a while back and the Jack Casady bass still uses the 50-250-500 level control if anyone has Casady electronics they'd be willing to part with. Here's some pictures of the original part:


[IMG][/IMG]


[IMG][/IMG]

Thank you for any assistance and have a great 2019 -Kev

[big_teee]

I think I would try Gibson's custom shop.
See If they have any idea how to restore it.
Or maybe they can source the parts?
http://www.gibson.com/Support/Repair...storation.aspx
T
**Anyone have any ideas?

[g1]

The Epi Jack Casady part sounds like the best bet to me.
I would think they must have that part, maybe they don't sell it without returning it to them for warranty (limited lifetime)?

[olddawg]

Not all old guitars are desirable or even valuable. That low impedance pickup setup was never even remotely popular for a reason. If it were mine, I would consider mounting some mini humbuckers on it and calling it a day. It is difficult to do do to much with it because, if it’s the one I think with the angled pickups, it makes standardizing it difficult. But if you have never tried to use one of those low impedance models.. you may be very disappointed after all of the trouble restoring it. I’m pretty sure you can kludge something together to test it and see if you like it. The one person I knew who owned one back in the day used a mic impedance adapter to plug into a normal guitar amp.

[Leo_Gnardo]

The one person I knew who owned one back in the day used a mic impedance adapter to plug into a normal guitar amp.

Was that Les Paul? I know he developed a low impedance balanced guitar, but the drawback was it needed a matching transformer at the amp end. OTOH he could plug direct into a mix console for recording. Les wasn't much interested in distortion. He had plenty of echo effects, overdubs & whatnot to dazzle the ears. Not to mention terrific playing technique.

[Chuck H]

Not all old guitars are desirable or even valuable. That low impedance pickup setup was never even remotely popular for a reason. If it were mine, I would consider mounting some mini humbuckers on it and calling it a day. It is difficult to do do to much with it because, if it’s the one I think with the angled pickups, it makes standardizing it difficult. But if you have never tried to use one of those low impedance models.. you may be very disappointed after all of the trouble restoring it. I’m pretty sure you can kludge something together to test it and see if you like it. The one person I knew who owned one back in the day used a mic impedance adapter to plug into a normal guitar amp.

THIS!^!^!^!^!^!^!^!

As guitars go, the "low impedance"/passive ideas that were occasionally kicked around literally NEVER worked out. Rendering such guitars in the "Mr. Microphone" category of collectibles. Novel, but sort of useless. I'd complete a conversion to standard type pickups and wiring. Save the original pickups in case a collectors market ever DOES develop for this model, or sell them to a true believer that MUST HAVE those pickups. At your discretion.

[olddawg]

Yep.. it was made to plug directly into a console using a balanced low impedance XLR cable. Had an XLR jack on the guitar. They were for “super clean” use. But for some reason not even the jazz guys liked them. They sound... “funny” imho.

[big_teee]

If it is this guitar? IMO it is a beautiful guitar.
I think you could rip it all out and install new pots, new pickups with pickup rings.
Don't know if it has a control access plate on the rear or not?
If you have to do it all through the f holes, it will be harder and more trouble.
T

[Bloomfield]

I suppose you could also make a little preamp and put it in there if there is room for the battery. That way you could stick with the original pickups for stock appearance, and it would be interesting to hear how they sound 'active.'

Andy

[olddawg]

This is the version I saw..

[g1]

[ATTACH=CONFIG]51748[/ATTACH]

This is the version I saw..

Thats a Les Paul Recording II. The signature is hollow like teee posted above.
The L5S was also a low impedance solid body.

[stairwaytokevin]

Hey, thanks for the replies everyone it's much appreciated I'll attach a couple pictures of the actual guitar I've got here below to avoid any confusion!

Cheers for the Gibson Restoration dept link big_teee; I've got a few contacts at Gibson here and in the USA that I've tried but I'll drop them a line as well just to be sure. The transformer in these is pretty unusual and would likely have only been manufactured for this model but I'll try pleading for a Casady board as well lol

I'm pretty well versed in how these guitars work (and how they sound, which I know is not for everyone) which is basically a Master Volume knob, Master tone knob, A rotary on/on phase switch, a three position 'Level' selector (the 50,250,500 ohm switch) a mono high impedance jack on the front to go to an amp, and the stereo low impedance jack on the side to run to a desk etc.

I know it's a possibility to change all of the electronics and pickups to something else but it would be a shame since I still have everything required except this one silly transformer. Plus, it's going to be very expensive to change everything including the pickups and it's not what my customer has asked for! If anyone's got a line on one of these little transformers or knows someone who can make one it really would be fantastic
Cheers, Kev

[stairwaytokevin]

Perhaps someone in the pickup maker section would be more familiar with low impedance line matching? It's an unusual request to be sure!

[big_teee]

Perhaps someone in the pickup maker section would be more familiar with low impedance line matching? It's an unusual request to be sure!

I'm a moderator in pickup makers.
I moved it over here.
Unless you are making pickups, more guitars are repaired over here in this area.
Also a lot of these guys also work on amps using transformers and the likes.
T
** I sent bbsailor a pm, he does low impedance pickups, maybe he will stop by, and can offer some ideas?

[g1]

The Casady is a current Epi model. For sure they have them, it's just a matter of finding the right person at Gibson to get your hands on one.
Good luck.