Fixed that on-or-off tone pot

WilburBufferson

Electromatic
Jan 23, 2017
26
Canada
I thought I would have to go through the pain of removing EVERYTHING to address this issue, but all I had to do was pull the tone pot through the F-hole without loosening anything else. Turns out that the pot was 500K (measured at 456K) and the cap was .022 uF. I attached alligator clips to test a range of values, but ultimately settled on a cap value of .005 which produced a better sweep through the range of the pot. I contemplated changing the pot to a brand new CTS 500K log pot (or linear) but didn't want to have to deal with enlarging the hole and searching for an imperial-sized knob, so I cut my losses. Works well if any of you have the same issue. BTW, the guitar is a 2018 Electromatic G5420, made in Korea.

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Kevin_28

Electromatic
Dec 16, 2012
24
California, USA

WilburBufferson

Electromatic
Jan 23, 2017
26
Canada
Now that I've spent some time with the guitar playing it in context, I've decided that I'm not satisfied. The .005 cap is not rolling enough of the high frequencies. Will have to try something in between, like a .01 value or something. While I'm at it, I might as well give the linear pot a try.
 

Wood Hollow

Electromatic
Apr 20, 2022
86
Indiana
Did you use aquarium tubing to relocate it, or were you able to do it by hand? Also, is yours the SW exclusive vintage orange?
 
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Lindo

Gretschie
Mar 10, 2019
115
Derbyshire
Linear pots are not going to give an even tone sweep.

How can it be worse than what I have now? Basically a mud switch that comes on at 2.

I have a 300k linear on the volume of my SG, and that is perfect. A very gradual rolloff of volume and a subtle reduction in brightness.
 

WilburBufferson

Electromatic
Jan 23, 2017
26
Canada
Did you use aquarium tubing to relocate it, or were you able to do it by hand? Also, is yours the SW exclusive vintage orange?

Actually, I used 5mm wide (detail) masking tape: stuck it around the pole, fed it through the hole and stuck the other end on the body so it wouldn't fall inside. Easy peasy.
 

WilburBufferson

Electromatic
Jan 23, 2017
26
Canada
Linear pots are not going to give an even tone sweep.

I've heard it both ways: lots of contradictory views out there. Two techs have recommended linear so I'm going to go with that. I think (can't remember) I have linear pots in my Tele Deluxe, but that has Les Paul controls and 50s wiring, so that complicates things. With 2V, one master V, and one tone, I wasn't sure how to do 50s wiring which would have been the least invasive option.
 

kdm1218

Electromatic
Jun 17, 2021
86
TX
I replaced linear in a 5435 in the tone knob, MV, and individual pickup volumes. Tone knob did basically nothing previously, and the others were like on/off switches, at least in that setup. Don’t think I own anything with linear.

Truly hope it works for you for what you’re after though!
 

mickeyg

Electromatic
Jan 20, 2021
4
Toronto
Wow, that's really interesting! I have the exact same guitar. It also had the "on-off-on" problem.

I took out the pot (same JinSung pot as yours) and measured the resistances across various points of the sweep with a multimeter. I found that midway through the pot the reading on the multimeter just dropped out; then the reading would come back again as I continued through the sweep. OK, so as far as I could figure out, it was a faulty pot. Or maybe I'm mistaken and it was just due to it being linear?

In any case, I took a deep breath and just yanked everything out and replaced with proper 500K CTS audio taper pots. I used the tubing method (you may have seen on youtube videos, etc.). A lot of little things to figure out, like where to get those tubes cheaply. Anyway, problem solved now and at least I know I've got decent pots in there. (While I was at it, I made the bridge tone into a no load).

I did have to get an inexpensive reamer tool to enlarge the holes for the CTS pots, which was quite easy to do, and the tool's since been useful for other little fixit jobs.

Glad you were able to solve your problem. Enjoy the guitar!
 

BCBlues55

Electromatic
Mar 20, 2021
7
Virginia
I have found that most of a tone pot’s effect happens at the low end (0-4) of the control. So I started using 250k pots for everything and got a much more usable sweep. It might be worth trying that too.
 

G-Point

Electromatic
Apr 17, 2022
5
Australia
I have found that most of a tone pot’s effect happens at the low end (0-4) of the control. So I started using 250k pots for everything and got a much more usable sweep. It might be worth trying that too.
500k pot resistance value is ok, just look for 20-30% log taper. Std 10% log is "to log". 20-30% log is closer to the linear taper but still log. The best compromise, but rare and more expensive to get.
 

G-Point

Electromatic
Apr 17, 2022
5
Australia
A capacitor is a capacitor is a capacitor
Except for ceramic "piezo driver" discs :). Some ceramic caps can be even sensitive to vibrations ! And ceramic caps provide much more audio distortion (not the best) than quality polypropylene or teflon caps. Forget about different, big dimension, high priced "snake oil" caps, it is just tricky commerce :).
 

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G-Point

Electromatic
Apr 17, 2022
5
Australia
Now that I've spent some time with the guitar playing it in context, I've decided that I'm not satisfied. The .005 cap is not rolling enough of the high frequencies. Will have to try something in between, like a .01 value or something. While I'm at it, I might as well give the linear pot a try.
Try different cap values around .01, it depends on the pickup parameters (generally inductance) and a little bit on pot value too. Original .022 almost always is too high value, cutting mids too. Try in between .082 and .015 values. The optimal value provides some "wah" effect, still providing singing jazzy mids. One more option is so named "no-load" pot (500k again), providing a little bit wider adjustment up (brighter) range.
 

6stings

Friend of Fred
Aug 14, 2010
6,186
Norway
I get mine on Ebay. try Russian made paper and oil or Orange Drops.

I still have these '80 Soviet military industry, paper-in-oil caps, greens and silvers, 010, 022, 033, 047. Bought a ton of them on ebay many years ago, the guys sold them in batches, so cheap. Some people sell these for like $10 a piece, if not more. I sold some too, 10 caps for $10 :)
By the way, these caps were not made in USSR, they were made for Soviet military industry, at old Tesla factory, in Trinec, former Czechoslovakia.
What Soviet army used them for is a mistery, but some of them are huge, you can shoot them from AK-47 :D
 

Lindo

Gretschie
Mar 10, 2019
115
Derbyshire
500k pot resistance value is ok, just look for 20-30% log taper. Std 10% log is "to log". 20-30% log is closer to the linear taper but still log. The best compromise, but rare and more expensive to get.

Bareknuckle sell them with 10, 20, and 30% tapers.


I've put the 500k 30% ones in and I'm taking them out again. Horrible. I've ordered some CTS 250k linear, and I'm ditching the tone control altogether. Wanted 300k ideally, but can't seem to find any. These'll have to do.
 


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