Gibson Historic potentiometer....

[Mark]

My pots came from CE distribution too.

[johnnyreece]

I thought I'd chime in with something I'd not seen mentioned (although, I will be honest...I read the first three and last three pages only). I'm using some Bourns push/pull pots on my LP. According to their datasheet, the taper is pretty dang close to the ideal line, although I've not measured actual characteristics. I think I've got four or so unused. If there's any interest, I can run through them real quick. However, they are metric shafts, if that's a dealbreaker for anyone. The price is pretty decent, though (under $5 each). Here is the data sheet:

http://www.mouser.com/ds/2/54/PDB183-GTR-220261.pdf

[Littlewyan]

But that datasheet says they have a 3/8" shaft just like the gibsons? Or are you talking about something else when you say metric.

[johnnyreece]

But that datasheet says they have a 3/8" shaft just like the gibsons? Or are you talking about something else when you say metric.

I was referring to the shaft size. Standards are 1/4", right?

[Littlewyan]

What Gibsons Les Pauls can you use the Historic Pots on? As I understand it most LPs use Long Shaft Pots except for the Historic Guitars. The historic pot is short shaft only so looks like you can't get away with using one in a Les Paul Traditional or a Standard. Am I right?

[bcmatt]

Ok, I installed four more in a friend's Epi LP Elitist: 500k, 515k, 521k, 521k.
So, my 12 Historics I've bought have been:
500k
511k
515k
521k
521k
525k
525k
531k
531k
532k
535k
539k

The Ephiphone Elitist LP and the Gibson Melody Maker LP both had routing close enough to the surface to fit these short shaft pots... well, I did scrape the MM a little bit to I could fit the washers I wanted to use...

[Littlewyan]

Well that answers that question. Sounds like its a gamble as to whether the pots will fit a std gibson. I've bought myself a 2014 les paul traditional and thought it might come with historic pots but seems doubtful as they probably wont fit unless on the off chance the wood is thin enough.

[rooster]

I just realized something? I had to replace a neck pickup volume pot in a Norlin Gibson ES335 the other day. And to my surprise, I found that this CTS branded pot, dated 1970, 24th week, is the exact duplicate of the Gibson Historic pot. Everything about it, brass shaft, retainer ring, collar, etc. are an exact copy.

So, this pot has nothing to do with anything 1959, something I had thought. Ha, it is a 45 year old copy so I suppose it can be considered 'historic'.

Oh, and I actually swapped the trace in the pot, not the entire pot, just to keep things looking correct. I also had to swap the shaft too, as the original had been totally ruined.

[rooster]

Something new on the pot scene: Emerson. Have any of you tried them? Stew-Mac sells them or you can buy them direct from Emerson. I did the later, purchased 4 pots including their Blender pot. The description from Emerson is really enticing "volume control down to 1 on the knob". Eh, made by CTS, just like the Gibby Historic, HOWEVER - in this case the the shaft does not have a retainer clip and this is something different.

Mine will be here Wednesday and I'll be back with a full report.

[Littlewyan]

They look good and quite reasonably priced as well. Can't wait for the report!

[rooster]

I received the Emerson pots today. I measured the 12 o'clock position of the 500k pot (actual measurement: 509k) and, where the Gibson Historic measures around 57k wiper to ground lug, the Emerson measures 141k. I opened the pots and examined the traces themselves. They are not the same - this is not a repackaged Gibson Historic pot.

At this point I installed the 500k version in my Tele Thinline RI (loaded with new MojoTone Wide-Range HBs). These pots are described by the seller as not a Centerlab clone, BTW, or the Gibson Historic pot but instead something that he and his crew decided on after testing quite a few samples from CTS. I was a bit dubious but the fine print says that the pots can be turned down to 1-2 and still produce sound.

Not to be limited to testing just the 500k pot, I also installed a 250k pot in my 52 Tele RI. It measures 248k overall and 68k at 12 o'clock. As a comparison, the current Fender issue 250k pot measures 234k overall, and 25k at 12 o'clock.

So these Emerson pots would be looking like a 25% audio taper pot perhaps, and not what the Centralab seems to be, a unique lineal/analog type taper according to some. Of course I have not measured the pot through notches 1-10 so I have no idea what the numbers there are that would produce a plot. Have we moved past this? Let me know.

But how do they perform in the guitars? In a word, WOW. The action is very very smooth, virtually drag free - something they stress in their description. Potting down is very even and there is audio down to the number 2 position. That slight drop from 10 (that a great pot can do!) is all there, too. I think it easily performs much better than the Gibson Historic pot and I would encourage others here to try them. Meanwhile I'm picking up some more.

[vibratoking]

I received the Emerson pots today. I measured the 12 o'clock position of the 500k pot (actual measurement: 509k) and, where the Gibson Historic measures around 57k wiper to ground lug, the Emerson measures 141k. I opened the pots and examined the traces themselves. They are not the same - this is not a repackaged Gibson Historic pot.

Thanks for the information on the Emerson pot. This indicates to me that the Emerson will not have a smooth turn on characteristic, which is the problem that the Gibson Historic pot solved. Look at the 5th post in this thread by geetarpicker. Based on your data, I already know the answer, but how does the Emerson perform in this respect?

[rooster]

Yeah, I was looking at those numbers....

Funny thing is, I just aquired 4 NOS vintage virgin Centralab 500K pots dated 3rd week of '57 and these read somewhat like the Emerson pots. Well, in fact, they are typically higher, reading 200K at 12 noon on the trace. Looking at Glenn's numbers this seems crazy doesn't it? What would this be, a 35-40% taper? I have yet to try these but I will very soon.

And here's the thing that my logic is getting hung up on. If the pot reads 10K at volume '1' or 14K at '2', (as in Glenn's second pot) how can the pickup have output? It makes sense to me that these lower numbers (1-4) SHOULD be higher if you want audio - the door swings both ways, right? I mean, in one of Glenn's examples, if the pot measures 500K, at volume '1' this would mean that 490K separates the output from the pickup. Looking at the NOS Centralabs, volume '1' is seeing about 40K to ground. That's 460K ohms of separation between the pickup and the output, and based purely on resistance this tells me the pickup would have to be louder in the second instance.

Haha, but then there's the vid of Glenn using his LP and things seem to be fine - (and more clearly in the neck pickup to me, FWIW).

But you asked about the Emersons and how they perform? Here's what I am finding and please read the second half of this paragraph. With the MojoTone WRHBs they are incredible, the 500K pots. And in the Tele (250K) this is true as well. I also got a report from another friend today who installed the Emersons in his Tele last night and he is also saying the same thing. We have both invested in Gibson Historic and RSGW pots over the years, btw. The Emersons are clearly BETTER. But here's the odd part of my response. In an Epi Elite with a 7.3 neck Pure PAF clone from Fralin, I have an NOS Centralab pot that measures 620K - and - and - it is unreal here! I have used 30% Hamers, RSGWs, and the Gibson Historic in this exact guitar - all measuring close to 500K - and the pickup always sounded anemic and dark, and more so as I potted down. This really puzzled/puzzles me. Is it purely the 620K load? Which is to say I am beginning to think that just maybe the typical Gibson PAF-type HB is a unique thing that needs a unique pot with a unique resistance value for the given pickup position.. I will try the Emersons on a trad HB soon, but for now, this is my report.


Oh, one more example. I am running the NOS Centralab pots (500K) in a Strat loaded with a T-Armond bridge pup and an old SC Melody Maker - two volumes, one tone pot, Gibson style. The Centralabs sound fantastic here so I can't imagine changing these out.

Buy an Emerson pot and give it a try yourself. I am convinced that this is a better pot for potting up/down than the Gibson Historic pot with ANY pickup.

[vibratoking]

There are several things going on, but the basic circuit is a voltage divider, which happens to be the volume pot. The output of the divider is the wiper. I think you actually need the resistance measurement at all ten settings to get a more complete picture of how the pot behaves in circuit. Measuring the resistance at the half way point is just one data point. I think we really care about how much the resistance changes as the pot rotates. This is what tells you how slowly or quickly it comes on or off. There are other issues, but this is number one for me. If this isn't to my liking, then I don't care about the rest. The Gibson Historic is the best in this respect AFAIK and the numbers in this thread prove that.

There are other issues like the total resistance, the rotational tension and the quality of the conductive track.

[rooster]

No worries. Fortunately/unfortunately, data on paper does not resolve sonic puzzles for me. For $7 it's not a big gamble.