Signal capacitor choices

[Jana]

If you want to see a visual representation of what I am talking about, go to the Duncan Tone Stack Calculator and select the James tab.

Change:

Zsrc = 6k
R1 = 1
R3 = 1
C2 = 1p
R4 = 1
C3 = 1p
C4 = 1p

(Changing a resistor to 1 ohm effectively creates a short, changing a cap to 1p effectively removes it. If I want to remove a resistor, I change it to 100M, if I want a cap to be a connection, I change it to 1000uf)

Then what you have is C1 = the bleed cap, R2 (Bass) = Guitar Volume, and R5 is the 1meg on the amp input jack.

This is not entirely accurate since it is not taking into account the inductance of the pickup, but it will be close enough to give a visual representation of what is happening.

[Jana]

different types of capacitors do sound different, not really a revelation, of course. I never paid much attention to it in guitar tone controls, maybe I should. I know in amps there is a significant difference in sound between say an orange drop and a mustard. Caps also go through a break in process in amps with the voltages that are applied to them. I don't see how a cap in a guitar can ever really be "broken in" given the voltage is in the range of about 100mv or less.

[billyz]

I have measured quite a few Black beauty caps and they all measure higher not lower. Typically a .02 measures .03 + . C Diaz liked to throw out the Red Herring .

Thankfully, I never bought into the WD40 he recommended.

I put in the Allessandro pots and a Black Beauty cap in my Nocaster and finally it responds like it should. Great tone wah control and nice volume sweeps, ala roy buchannon.

[selloutrr]

a great place to find old Back Beautty caps is from old RCA test equipment i bought a Tone generator on ebay a couple years back for $10. when i fired it up it wasn't holding a steady frequency so i opened it up and it was packed with $$$ caps. I put in new mallory 150 yellow dew hickeys and reformed most of the vintage caps and found them better homes in some amp projects.

Another great cap for the $ are the ones you can buy on the sale/trade post. I picked up a few pairs and i was surprised on the improvement. I'm not sure I would change out anything on an instrument with vintage collecting value, but for a players instrument they are well worth the listen!

[67plexi]

All MY stage guitars not my vintage guitars. I use 1950's bumble bee
capacitors. First gut out all of the stock parts, Replace the stock pickups with JM Rolph, secound replace the pots. with CTS or Stackpole.
Then 1950's mod. The tone controls and volume act like a blend control
I never use the tone conrol but the sound can't be beat.
It is great to get this sound out of new guitars.
Maby other capacitors will do this smoothing out the signal. I have used
alot of the new capacitors made like the old just didn't cut it.

[rooster]

Jana - Hi. I enjoyed your posts and have considered this idea of yours, the circuit you designed, for my gtrs. One problem, running the historically correct LP wiring, I cannot use your idea. Notably, the deal breaker is the fact that the tone pot is not grounded like the Fender example you drew. With me?.

I may give this a go with one of my Strats but I know I won't be changing my LPs. Still, the idea looks great on paper, you know? Take care and thanks for sharing.

BTW, for those who haven't seen this, this is pretty definitive. Please note 3 different LP wiring examples over the years. The '59 model is with the wiper of the tone control attached to ground. This is the one I use in my LPs. http://www.singlecoil.com/docs/paula.pdf

[Noel Grassy]

I've been using 220K paralleled w/ 220pf for the volume pot doodad.

Has anyone tried Ken's "Tone pot removal" trick? Removed by scraping the final 1/8" off the pot's carbon track. So when you roll full-up on the tone, she's-a-bypassed. It seems so simple and Spartan for such an improvement.YMMV

[drz400]

I've been using 220K paralleled w/ 220pf for the volume pot doodad.

Has anyone tried Ken's "Tone pot removal" trick? Removed by scraping the final 1/8" off the pot's carbon track. So when you roll full-up on the tone, she's-a-bypassed. It seems so simple and Spartan for such an improvement.YMMV

I have done that, first heard about it from Fralin many years ago.
You only need to do a very small cut
Only problem is I dont really like the extra glass from this mod

[Tin Ears]

This same mod is called the fingernail polish mod on another forum. No cutting required. Just open up the pot and place a small drop of fingernail polish on the resistive element inside the pot where the pot's wiper would be when the pot is turned all the way up. It works great!

[Markusv]

Last night I placed a treble bleed in my Godin SD - strat wannabe
It is a great guitar as is and remarkable value for the money and made in Canada -eh!

The cap I used was a Polystyrene film 470pf across the volume pot.

Holy crap!!
The guitar "opened up" and now the tone control is way more useful. That is something I did not expect- I thought it would only impact the treble roll-off when I turn the volume down, but I am hearing a certain clarity and sparkle that was not there before.

Thanks Jana and everyone else who contributed on this topic

BTW I also plan to do the same with my Yamaha SBG 200 (Les paul/sg Copy)

[Structo]

Tin Ears and drz400,

That is called a no load pot.

They actually make them like that.
But cheaper to make yourself.
Like mentioned, you only have to remove enough of the trace where the wiper rests at the end of it's travel.

It completely removes the pot from the circuit when dimed.