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need help with '59 centralab pots

A-tony

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Joined
Jul 12, 2006
Messages
463
Hi,
calling help from all burst owners/experts/repairmen etc : I have a set of Centralab pots from late '58, they all read from 511K to 604K, I was looking after '59 ones but all I could find was original centralab pots that, still C2, read from 610K to 680K (!!!).
As lettering on all these ones is on the back instead of the classic side one, Im asking if pots on '59 burst usually read so high.

Many thanks for all the data you can share
 

lewis_grey

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Joined
Feb 14, 2016
Messages
45
I seem to recall reading that they varied a lot (as with most stuff from the 50's!) and often read a fair bit higher than 500k, but I don't have first hand experience.
 

Cream Fan

Active member
Joined
May 1, 2003
Messages
2,695
I have a set of '56 Centralabs in my '03 Historic Makeover and they sound killer, better than any modern pot. Don't worry about the date, those pots are GOLD! As for the higher value, that's not uncommon with vintage pots. The crux of the matter is they will still be clearer and more 3D sounding than anything new from CTS.
 

renderit

Well-known member
Joined
Jan 19, 2009
Messages
10,951
I have a set of '56 Centralabs in my '03 Historic Makeover and they sound killer, better than any modern pot. Don't worry about the date, those pots are GOLD! As for the higher value, that's not uncommon with vintage pots. The crux of the matter is they will still be clearer and more 3D sounding than anything new from CTS.

+100 though I don't profess to know why...
 

A-tony

Member
Joined
Jul 12, 2006
Messages
463
thanks for all replies but I must ask (sorry for being so picky) can you please post ohm rfeadings for all the '59 pots you have or put your hands on? it will be very helpful for me
thanks again
 

hogy

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Joined
Nov 4, 2005
Messages
715
I've posted this before, the resistive element inside those old pots is mainly compressed carbon. As the wiper slides over that carbon trace, microscopic amounts of material are worn off. The thinner the carbon wears with time, the higher the resistance becomes. If you want to picture an analogy in your mind, it is like pinching a garden hose. The same amount of current has to pass through a smaller amount of carbon, the resistance goes up.

So, nothing lasts forever. 1950s pots that started out reading 500k 60 years ago, will read much higher today, if they have been used. I've seen them up in the 900k range in very well worn guitars.


As to why the old pots sound better (they do), I'm not entirely sure. My guess is it's the chemical composition of that carbon trace. It's not just carbon, there are binders and other agents in there as well. Supposedly, from what I heard but cannot verify, there's a good amount of lead in those old potentiometer elements. Which would explain while modern RoHS compliant pots are not the same and never will be.
 

garywright

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Aug 17, 2002
Messages
15,584
thanks for all replies but I must ask (sorry for being so picky) can you please post ohm rfeadings for all the '59 pots you have or put your hands on? it will be very helpful for me
thanks again

I acquired a full set a couple years ago and the least was around 600k up to 770
 

Dave P

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Joined
Oct 13, 2001
Messages
976
C2 is the taper curve, they had a few to choose from in the old Centralab catalogs. I stumbled onto a small cache of NOS 500k C2 taper Centralabs a few years back, and most of them read over 500k, and these had never been used.
 

A-tony

Member
Joined
Jul 12, 2006
Messages
463
C2 is the taper curve, they had a few to choose from in the old Centralab catalogs. I stumbled onto a small cache of NOS 500k C2 taper Centralabs a few years back, and most of them read over 500k, and these had never been used.

may I ask you to share exact readings of some at least? thanks
 

springhead

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Feb 12, 2016
Messages
262
Can't measure volume pots without desoldering. Tone pots have one end free though. Mine are late '59, bridge = 630K neck =790K.
 

springhead

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Joined
Feb 12, 2016
Messages
262
Can't - pot is in parallel with the pickup. You'll just get a measurement that is very close to the DC resistance of the pickup winding.
 

thin sissy

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Jan 2, 2006
Messages
2,691
Sometimes when I play my 57 Jr after a while of playing other (new, but great) guitars, I'm almost annoyed by how good the old pots are compared to everything else I've tried. It's hard to say exactly what it is that makes them better, but it's very apparent when you play. Maybe it's the pickup too though, who knows?

I dread the day these pots wear out, what are the next best things any of you have tried?
 

geetarpicker

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Jan 14, 2003
Messages
812
The original Centralabs in my '59 stinger burst measure 500k, 589k, 643k and 888k. This being the burst many folks have seen in my Trainwreck amp videos on Youtube. The two higher pots are on the tones, and though some of the resistances perhaps went higher with use I sort of doubt the tones were messed with more than the volumes. My gut feeling is these were simply all over the map when they were new. That said, it seems later (early 60s-70s) Centralabs typically started to run lower on average than the early ones. At least that I what I've run into.
 

Tom Wittrock

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Aug 2, 2001
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42,567
The original Centralabs in my '59 stinger burst measure 500k, 589k, 643k and 888k. This being the burst many folks have seen in my Trainwreck amp videos on Youtube. The two higher pots are on the tones, and though some of the resistances perhaps went higher with use I sort of doubt the tones were messed with more than the volumes. My gut feeling is these were simply all over the map when they were new. That said, it seems later (early 60s-70s) Centralabs typically started to run lower on average than the early ones. At least that I what I've run into.

Did you unsolder them to measure them? :hmm
 

geetarpicker

Member
Joined
Jan 14, 2003
Messages
812
Did you unsolder them to measure them? :hmm

Yes, pickup leads were both unsoldered from the volume pots to test. Also I used a decent Fluke model 112 digital meter. The pots appear original to the guitar and all have matching 1959 date codes. That said I changed the pickups back in 1985, so that is the reason I was not worried more recently to disconnect the hot pickup leads to test the pots. The solder joints had already been broken 30+ years ago.
 
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