The capacitor thread.

[FF_Pedals]

Here is a plot of the dielectric constant of engine oil vs. the degradation (age) of the oil:



Here's the forumula for a parallel plate capacitor:



The dielectric constant is epsilon-r.

Maybe this data can explain why NOS paper in oil capacitors 'drift' upwards in value?

[jonesy]

IMHO the upwards drift in some PIO caps is caused by two things...

A. The natural drying and thickening of the Oil over the years.

B. Used caps (Pulls) that were used in high voltage circuits where the Oil get's cooked will also change reading dramatically.

Many vintage caps (Bumble Bees) I have tested are very close to original specs and have not changed much at all. Generally a new capacitor will most always read below what it is rated for.

[jonesy]

Originally Posted by FF_Pedals

Oh, the test conditions are far from what these capacitors would see in a guitar. The author of the link mentions he used the test setup to amplify the measurements for plotting purposes so the results are easier to see visually. I would think that the most important factor for us would be the curve of the dielectric "constant" over the audio bandwidth. I've read that paper in oil is the most linear, I haven't seen those graphs though.

I have found Ohm rating on pickups used, Value of Pots, Rating of capacitor and EQ Settings on Amp will all cause varying results in a guitar circuit. Even with PIO caps I have noticed (with my ear) peaks and curves in Tone when Rolled-off

[FF_Pedals]

Sweet. Mine measure very close. They were pulled from an organ so unless they were part of the power amplifier I'm assuming it was a low voltage signal application. The readings are very close. Slightly high but as you said this is just from the aging of the oil over the years. I guess some could misleading think that a 0.022uF rated PIO cap sounded warmer than a new 0.022uF cap because the value has drifted up slightly and actually filters more of the highs. I think the 0.015uF bumblebees I got read 0.016uF. I bet they will be the best out of my test group.

[Emiel]

Ok, I now can share my experiences with PIO caps.

I never thought they would make a huge difference but a few days ago I putted two 'TAD 0.02uf Vintage Paper in Oil capacitors in my '93 Les Paul. First sight: they're like ten times bigger than the stock ones!!

And yes, after trying them for a few days, I do hear a difference. The sound is a bit more 'vintagey', the highs are rounder, less harsh. Overall it seems to be a bit warmer and smoother sounding with the caps as well. It makes the guitar less suitable for metal though. Instead my guitars excels even more for '60s and '70s blues/rock sounds. The tonepots do work different too, with the pots at zero you don't get the overly dark, muddy sound any more. Instead you you get... yes the so called woman tone. You still retain some highs with the tonepots at zero. So the caps seem to make the tonepots more usable if you call me.

It was definitely worth the 6,5 euro I paid for it. The caps did change the sound a bit, in a very pleasant way. I still would like to brighten up the neck pickup a bit though. I mostly leave the tonepot on that pickup on 10 and sometimes I wish it could be a bit less fat and smooth... but I'm really happy with the geetar... even more than before

[essguitarman]

I just put in new vitamin q's .022 uF from all parts and i really like them... havent tried out to many caps just compared with bumble bees and ceramic disc and i really like the vitamin q's....wat do ya'll think of em...worth tryin out more kinds of caps...or since i like how the sound, ust stick with em

[essguitarman]

i might add that theyre in my lp junior...

[FastRedPonyCar]

Hey guys I thought I would chime in and ask a couple of questions on this subject.

First, What I have: 09 tokai LS150 w/stock pickups and orange drops (assume .22 but not sure), also have a set of the .22 WCR caps, also on hand are about 5 or 6 various value orange drops.

Bought (on the way): RS vintage wiring kit w/superpots & Jensen .22/.15 PIO's (bought primarily for the better pots but for the price I wouldn't mind having a couple caps to try)

Also being built is a set of the BK signature Sheptone pickups.

On the way from ebay:

2 NOS .027 300v C-D Vitamin Q Type Capacitor Paul SG - eBay (item 370155005185 end time Sep-03-09 00:52:10 PDT)

2 NOS .015uf 400v Soviet Military PIO Caps Les Paul 335 - eBay (item 350163332240 end time Aug-05-09 19:04:35 PDT)

I've also got .01 / .015 / .022 / .047 / .1 value workalike bee replicas coming from dirk at singlecoil.com I'm interested in hearing these.

I'm also wanting to try out vintage bees but would be more interested in trying before buying just to test them vs these other ones.

I'm getting several varieties to basically test and try out to see which ones I like.. who knows I may end up with two different brands/types/values for the neck and bridge so I'm trying to not just jump on one particular bandwagon. If I end up with a set of NOS bees in it, great but I will be more at ease subconsiously knowing that had also tried out numerous others that people say they love.

That being said, are there any other inexpensive options I should try out?

The Premier guitar cap shootout had favorable things to say about the Mallory's (I assume nos) but I can't find them anywhere.

[freddarl82]

I picked up this set of caps recently:

They look like the real deal to me. Anyone have any info to the contrary? The price was right; I paid $48 for all 6. I do not have a tester to really check them out, so I guess I will have to just try them. How would they likely stack up against the Luxe repro Bees from RS currently in my 57 Historic Goldtop (assuming they are "in spec")?

Now just trying to decide where to put them...even though I promised to sell a pair to a friend...Hmmm...

[jonesy]

The Original PIO Black Beauties in the 60's were marked 160P .022, a lot of mylar caps were in circulation at that time as well.

[freddarl82]

Originally Posted by jonesy

The Original PIO Black Beauties in the 60's were marked 160P .022, a lot of mylar caps were in circulation at that time as well.

Thanks, Jonesy, but can you elaborate on what these might be?

Four of them say (reading around the cylinder):
SPRAQUE
.02MF +/- 10%
600 VDC
6TM-S20
.02MF +/-10%
600 VDC

The other two say (all letters in a smaller font than the other four):
SPRAGUE
.02 MF +/-10%
600 V.D.C.
6TM - S20
160P
.02 MF+/-10%
600 V.D.C.

If it makes a difference, I've tried to present these as accurately as possible, right down to spaces and periods (VDC vs. V.D.C.). The +/- has the "+" directly over the "-", but my keyboard does not have a way to present that accurately. The covering on all of them appears to be relatively glossy plastic, including the ends.

So, do you think these are PIO, Mylar, or something entirely different, and what might I expect of them?

Thanks in advance!