Need advice on Gibson L-5 pots and cap

[Chi]

Hi folks..
Wonder if I can get a little help please.
Bought a Gibson Custom L5 Wes Model, (£12.5k) but it's not sounding quite right. Acoustically it sounds great but plugged in the tone is not really as round, warm or lively like others sound of the same model I hear everywhere.

I have tried 5 different string types and several different amps including hand wired Fender Twin, Deluxe, Princeton) and solid state (Roland Jazz Chorus, Henriksen but still not singing as it should and is a bit dull, muted and not very lively.

And I think I may discovered why.. I took the pots and wiring out and discovered this absolute awful mess with the electrics. The plastic shielding on the wires is all
melted and burnt. Someone has changed the original pots and cap on this guitar and replaced them with this absolute junk with the soldering looking like it was done by a 5 year old.
You can see here the terrible soldering mess on these pots someone has done and not declared and seems it's been 'rewired' at least 3 or 4 times.

These also look like the cheaper lower quality Alpha pots whereas Gibson on L5 guitars, being high-end archtops, usually used better quality potentiometers, I think CTS brand pots.

So I am trying to find the original pots and cap that was used when this guitar came from the factory in the early1990's as I now have to replace the entire wiring loom to try get this guitar to sound as it did when made.

Can anyone help please with any info on what the ORIGINAL pots and cap were on this guitar or what good quality pot and cap would work so I can try get it back to its former glory?

Thank you.

[58flame]

Even after you switch out the pots and caps it might not sound all that different. How does it sound with the controls on 10?

[GuyBoden]

Pre Wired Les Paul Junior Kit

Pre-Wired Les Paul Junior Wiring Harness




This is a standard Gibson Les Paul Junior style kit with short shaft potentiometers.

Included:
(2) CTS 500k vintage taper audio short split shaft 7% tolerance potentiometers
(1) Switchcraft mono input jack
(1) Mojotone Dijon .022uf capacitor

[Chi]

Hello Guy...

What pots and cap would you recommend to go in this guitar?

It does not sound like any of these that's for sure..

https://www.youtube.com/watch?v=MEDU4lrv51U


https://www.youtube.com/watch?v=IGKIyH6Im8A&list=RDIGKIyH6Im8A&start_radio =1


https://www.youtube.com/watch?v=d7ejuIqBIzg


https://www.youtube.com/watch?v=Kb6FSqjM6xg&list=RDKb6FSqjM6xg&start_radio =1


https://www.youtube.com/watch?v=_nwEBrQRY_o

[Chi]

Oh wow you posted as I was posting..

That will work well yes?

[Chi]

Would this work just as well as I am in the UK..

PRE-WIRED GUITAR WIRING HARNESS | 50S LES PAUL JUNIOR KIT | RIGHT HANDED

Pre-Wired Guitar wiring harness | 50s Les Paul Junior kit | Right Hand – James' Home of Tone

- 2x CTS '450' Series +/-10% Tolerance audio taper short shaft pots - 500k split shaft
- 1x .022uF 'Yellow Mustard' type tone capacitor
- 1x Pure Tone multi contact jack socket (nickel finish)
- Gavitt USA made Braided 22AWG wire
- Soldered using R-Tech Premium Lead-Free (Sn95.5Ag3.9Cu0.6) 22swg Solder wire
RoHS Compliant
- For optional ground wire - Gavitt 22awg black cloth covered wire

[Jimmy Mack]

The above photo looks like the "ticket" AS LONG AS there is enough wire from the pots to the output jack! And don't forget to ground the tailpiece ( an extra wire).

Sorry that you got lead into such a mess. No wonder your tone is escaping somewhere along the line. Looks like the pot in your hand is not a 500K ohm pot, which would be better than the 300K or 320K pots Gibson has used in the past.

Did the previous owners also rip out the original pickup?? If they did, that may also be where your tone went!

[garybaldy]

Does the guitar have the original pickup?

[GuyBoden]

Would this work just as well as I am in the UK..

PRE-WIRED GUITAR WIRING HARNESS | 50S LES PAUL JUNIOR KIT | RIGHT HANDED

Pre-Wired Guitar wiring harness | 50s Les Paul Junior kit | Right Hand – James' Home of Tone

- 2x CTS '450' Series +/-10% Tolerance audio taper short shaft pots - 500k split shaft
- 1x .022uF 'Yellow Mustard' type tone capacitor
- 1x Pure Tone multi contact jack socket (nickel finish)
- Gavitt USA made Braided 22AWG wire
- Soldered using R-Tech Premium Lead-Free (Sn95.5Ag3.9Cu0.6) 22swg Solder wire
RoHS Compliant
- For optional ground wire - Gavitt 22awg black cloth covered wire

Looks good. That's a bespoke harness builder, so you can also:

1. Specify wire length between pots.
2. Specify wire length between Pot to the output jack.
3. Specify wire length to ground Tailpiece.

[rpjazzguitar]

I'm wondering if you can connect the pickup (or neck pu) right to the output, as a test to see what it will sound like with all pots maxed.

Perhaps someone can explain how the messy wiring sucks tone while still working at all. Maybe the pots leave in some ohms of resistance when they shouldn't? That would sound like the correct electronics set somewhere other than on 10.

I'm thinking to take a good look at the pickup, assuming that the guitar sounds like it should acoustically.

[Stringswinger]

I understand where the OP is coming from. Many years ago, I bought a Super 400CES (I still have it) and was never fully satisfied with the tone. At one point, I had decided to sell it and pulled the pickups for a pre-sale detailing. I found that the guy I bought the guitar from (who told me that he sold the Super 400 to fund a Benedetto) had replaced the neck pickup with a Benedetto pickup and never disclosed that to me. I sourced a Gibson 57 classic pickup from the same era as my guitar and had it swapped. Away went my plans on selling that guitar.

I suspect that once the wiring harness and pots/jack is replaced, assuming the pickups are correct, the OP will love his guitar. People who modify their guitars have a duty (legal and moral) to disclose those changes to a buyer. Those who do not are simply bad people and perhaps their Karma will catch up with them.

To the OP: Good luck!

[deacon Mark]

I was going to say this is relatively simple. A 57 Classic pickup is needed so assuming that you have this that if fine. Then you wire with new CTS pots 500 and correct cap. and it is done. With one pickup is really easy although I would just go the route of getting the prewire solderless kit you might have to add length on the output jack or ask them to do it for you. When completed it should sound great period.

[nevershouldhavesoldit]

Perhaps someone can explain how the messy wiring sucks tone while still working at all. Maybe the pots leave in some ohms of resistance when they shouldn't? That would sound like the correct electronics set somewhere other than on 10.

You're right - messy wiring will not suck up tone if it's mechanically sound and electrically conductive. But poor soldering can affect tone, although a joint would have to be really bad but still partially conductive to do so. Joints that are "dry" (ie have too little solder) or that were overheated during soldering can be partially conductive and have finite resistance (i.e greater than the zero resistance a well done joint should have). If the solder joint was not mechanically tight and sound, and there was any space between the joined metals, any nonconductive buildup like flux, oxidation, or corrosion can turn the joint into a capacitor - the grunge is the dielectric.

The other common problem with solder joints is that the joint was not mechanically secure and stable, so at least one of the pieces shifted slightly while the solder was solidifying. This changes the crystallization of the solid solder and can leave it partially conductive or completely cold. The giveaway to this is solder that turns dull rather than shiny as it cools and solidifies.

I can't tell from the pic where the tone cap is inserted into the signal path in the frankenharness. Depending on how it's wired, rolling off the volume may or may not affect tone.

[rpjazzguitar]

You're right - messy wiring will not suck up tone if it's mechanically sound and electrically conductive. But poor soldering can affect tone, although a joint would have to be really bad but still partially conductive to do so. Joints that are "dry" (ie have too little solder) or that were overheated during soldering can be partially conductive and have finite resistance (i.e greater than the zero resistance a well done joint should have). If the solder joint was not mechanically tight and sound, and there was any space between the joined metals, any nonconductive buildup like flux, oxidation, or corrosion can turn the joint into a capacitor - the grunge is the dielectric.

The other common problem with solder joints is that the joint was not mechanically secure and stable, so at least one of the pieces shifted slightly while the solder was solidifying. This changes the crystallization of the solid solder and can leave it partially conductive or completely cold. The giveaway to this is solder that turns dull rather than shiny as it cools and solidifies.

I can't tell from the pic where the tone cap is inserted into the signal path in the frankenharness. Depending on how it's wired, rolling off the volume may or may not affect tone.

Thanks for this explanation. I didn't realize a poor joint could introduce capacitance. If that was in series with the volume pot, what would that sound like? Tinny? Much too quiet?

Do I understand correctly that reheating the solder joints would solve that problem? (I understand that, in the OP's case, that might not be enough, given low quality pots and what seems to me might be a questionable capacitor - not to mention the mechanical strength of the whole harness). But, in theory, in a guitar with easy soldering access, would the first thing to do be to reheat the joints?

[buduranus2]

Would this work just as well as I am in the UK..

PRE-WIRED GUITAR WIRING HARNESS | 50S LES PAUL JUNIOR KIT | RIGHT HANDED

Pre-Wired Guitar wiring harness | 50s Les Paul Junior kit | Right Hand – James' Home of Tone

- 2x CTS '450' Series +/-10% Tolerance audio taper short shaft pots - 500k split shaft
- 1x .022uF 'Yellow Mustard' type tone capacitor
- 1x Pure Tone multi contact jack socket (nickel finish)
- Gavitt USA made Braided 22AWG wire
- Soldered using R-Tech Premium Lead-Free (Sn95.5Ag3.9Cu0.6) 22swg Solder wire
RoHS Compliant
- For optional ground wire - Gavitt 22awg black cloth covered wire

Uh-uh. You want audio taper for the volume but LINEAR taper for the tone.

[Spook410]

Didn't some Gibsons have 300K pots? Don't recall which models or time frame.

[58flame]

If you want it to sound lively, consider a Seth Lover as well as a 57 classic. 57 classic is correct for that guitar, but I think Seth lovers are a bit livelier.

[nevershouldhavesoldit]

Thanks for this explanation. I didn't realize a poor joint could introduce capacitance. If that was in series with the volume pot, what would that sound like? Tinny? Much too quiet?

Do I understand correctly that reheating the solder joints would solve that problem? (I understand that, in the OP's case, that might not be enough, given low quality pots and what seems to me might be a questionable capacitor - not to mention the mechanical strength of the whole harness). But, in theory, in a guitar with easy soldering access, would the first thing to do be to reheat the joints?

Any time a pair of conductors is separated by a nonconductive medium, they form a capacitor. Admittedly, it's a very rare joint that's bad enough to add resistance and capacitance yet still conduct electricity. Epending on wherethe joint in question is located, it can act the same or the opposite way from cable capacitance. Cable capacitance bridges the signal lead and ground, so it drains the highs in the signal to ground. But if the capacitor is in the signal path and not bridging it to ground, it will be a high pass filter and reduce lows. So if the offending joint is in the signal path, it will make the signal brighter (or tinny or however you hear the effect of lost lows). Cable capacitance is expressed in farads per foot of cable, and it takes a pretty long cable to audibly affect tone.

I suspect that a really cruddy solder joint with a fair amount of buildup between the soldered wires has more capacitance than a similar length of guitar cable, but it probaboly has lttle audible effect by itself. But remember that there's resistance involved too. When you combine resistance and capacitance in various ways in a circuit, you create an RC filter - and that probably has some audible effect in the uncommon event of a perfect storm of bad soldering.

Reheating the joint (which is called reflowing) to melt the solder is not a good way to deal with this for many reasons. Any debris from a bad joint is still in the solder and will weaken the joint. If the metal components weren't heated enough for the solder to melt and flow over them (which is pronbably the most common cause of bad solder joints), the surfaces of the metals to be joined are not sufficiently wetted with liquid solder to form a good bond. Any motion in the cooling joint will cause crystalline anomalies that further degrade the joint. The best way to deal with a bad solder joint is to heat it enough to disassemble it and remove all of the old solder. Clean metal surfaces like the back of a pot with a very fine emery cloth that doesn't leave dust. Trim off badly tinned wire ends, strip a bit more, and start fresh. If there's not enough length left to do that, use a new piece of wire.

It is acceptable to reflow some kinds of soldering jobs, eg certain PCB eyelets. But it's still better to use a solder suction tool to remove the hot solder and use fresh. It's common for techs to reflow grungy looking connections in old tube amplifiers, b ut it's still better to suck out the solder and use fresh if you'e not going to clean and redo the joint. Soldering is not as simple as most people think and errors are common. Reflowing joints between wires or between wires and flat surfaces like the backs of pots is generally a bad idea.

[Jimmy Mack]

SO you have a great guitar to start with, and yet the electronics bring it down.

Your mission here is to analyze every aspect of those electronics from the p/up to the output jack. AT this point it doesn't matter if Gibson used improper or shoddy materials or if amateur hobbyists screwed up the system!

Plenty of info available here and elsewhere. Your pots may have been burned inside - in those shoddy soldering forays. Same with the capacitor

Best thing to do is analyze, gut, and replace (electronics) with reliable elements, go slow and check all of your work.
I've had to do it on an L5 and a C shop Les Paul Custom, as I'm sure many others have.

[58flame]

SO you have a great guitar to start with, and yet the electronics bring it down.

Your mission here is to analyze every aspect of those electronics from the p/up to the output jack. AT this point it doesn't matter if Gibson used improper or shoddy materials or if amateur hobbyists screwed up the system!

Plenty of info available here and elsewhere. Your pots may have been burned inside - in those shoddy soldering forays. Same with the capacitor

Best thing to do is analyze, gut, and replace (electronics) with reliable elements, go slow and check all of your work.
I've had to do it on an L5 and a C shop Les Paul Custom, as I'm sure many others have.

This exactly. Doubtful the pots and caps make that much difference. Yank it all out, put in a brighter pickup and your pots/caps of choice and call it a day. If you still don't like it - guess what? It's the guitar. Many of us have been there as well. I can think of 3 guitars I wanted to love but couldn't make sound the way I wanted.



Good luck.

[Strat-itis]

From the pic of the wiring, I would say it's ugly soldering, but that it is NOT sucking any tone. Like NSHSI said, the solder joint has to be partially conductive to suck tone. If it's fully conductive, it will not suck tone regardless of how pretty it is. Although it's still nice to have a tidy soldering job on your guitar.

Also, the 'quality' of the pots don't contribute to the tone ime. Just get something that you're happy with spec, tolerance, and durability wise.

If you want a warmer sound, you can simply bump down the value of your pots.

300k is still quite zingy but is noticeably warmer than 500k. Will absolutely not hurt anything if you want to go warmer but be conservative.
250k is kind of a medium ground with some warmth and still some brightness.
There is also 200k which will start to get in the fully warm zone.
100k is super warm and smoky but still has enough detail on top. I highly recommend it for jazz guitars. Seriously hardwires in the warm, smoky tone. Noone ever takes me up on this tho. The value is too low to use for a tone pot, it has to only be used for a volume pot.

Now, the circuit looks to have a ceramic cap. This is debated, but I believe the ceramic caps to work decently, but to sound a tad worse than 'quality' materials like orange drop and pio. So that can cause tone suck in the circuit, as with a tone pot that isn't no load, it'll still filter some signal even with the pot on 10.

[Spook410]

- I'm in the camp that says you cannot hear any difference in capacitors in an application where they only serve to shunt signal to ground. If the cap is good, sounds the same in a guitar as any other with the same value. That being said, I use orange drops because they look cool.

- A 250K pot tone pot is typical for single coils. Along with the difference in cap values it helps rein in the brightness.

- From user 'In the Light' on a Les Paul forum. Not checked for full accuracy (but I think it probably is) and posted back in 2008:

• Gibson installed 500k Tone and 500k Vol pots on all guitars up until mid-1973.

• Beginning mid-1973 Gibson was using 300k pots for both Vol and Tone.

• Then from approximately 1977 thru the late-'80s Gibson was using 300k Vol pots with 300k or 100k Tone pots!

• The stock Vol pots starting circa-1990 thru today for all Standard production models (not Historic or Custom Shop) are 300k linear-taper, and Tone pots are 500k audio-taper.

• Historics and Custom Shop Les Pauls use 500K for both Vol and Tone pots.

[Chi]

Looks good. That's a bespoke harness builder, so you can also:

1. Specify wire length between pots.
2. Specify wire length between Pot to the output jack.
3. Specify wire length to ground Tailpiece.

Well, I've always found Gibson 59 Classics to be a tad dull and muted, or maybe I've just heard bad ones.. or maybe the one in this guitar despite appearing to be original just didn't sound right due to someone completely messing up the insides. The 59 in it does seem to be original but after what saw inside this guitar nothing would surprise me.

I swapped the pickup for a Gibson CustomBucker under-wound/unpotted and that improve things quite massively but still not quite there yet. I have some hand built pickups made for me by Kent Armstrong based on the original 59 Classic that ware waiting in the wings just in case.

The picture I sent you from the loom was a sample that would fit and Les Paul Junior similar to what you showed me.. but the guy that makes them is going to make one specifically for my guitar. So we took all the measurements of the distance between the pots, the distance from the tone pot to the tail bridge, and the distance from the volume pot to the neck pickup so we can get all the braided cable lengths correct. He also adds an additional ground cable so the thing is entirely complete and just needs slotting into place basically.

I'm really hoping that this loom will be the last thing I need to do to get this guitar sounding beautiful.

[Chi]

Thank you Strat for these additional details..

Message from loom builder as to what we are starting with.

Quote:

Thank you for confirming and thanks very much for the wiring order, look forward to making it for you

Just to confirm the specs I'll be making it to, I'll list the details below -
L-5 Wes Montgomery V-T 6.3/6.4cm T-J 10cm
CTS 450G series 500k split short shaft pots (tested for as close to 500k for the pair as possible)
Switchcraft mono jack
Jupiter Condenser USA made PIO bumblebee .022uF cap Gavitt
USA 22awg braided wire
Supply with pre-wired ground wire in case it's needed 'Modern' wiring style.

If this still does not get me there I will try some of your suggestions to put me in that warmer direction thank you.

[GuyBoden]

"Good Tone" is a very personal thing.

In the past, I've created simple test wiring rigs, so I could test various Caps and Pots values.