FDP Home Page / FDP Forum / FAQ's

The FDP is made possible by the following companies and individual members like you.
Please use the links below to show them we value their sponsorship.

Musician's Friend

Guitar Center

Amazon

Jensen Loudspeakers

Amplified Parts

MOD KITS DIY

Sweetwater

Antique Electronics Supply

Yellowjackets Tube Converters

WD Music

Apex Tube Matching


* God bless America and our men and women in uniform *

* Illegitimi non carborundum! *

If you benefit and learn from the FDP and enjoy our site, please help support us and become a Contributing Member or make a Donation today! The FDP counts on YOU to help keep the site going with an annual contribution. It's quick and easy with PayPal. Please do it TODAY!

Chris Greene, Host & Founder

LOST YOUR PASSWORD?

......................................................................

   
FDP Jam
Calendar
Find musicians
in your area!
  Search the Forums  

FDP Forum / Guitar Mods, Repairs, and Projects / 33 or 47pf capacitor

Next 20 Messages  
Therealfrogman
Contributing Member
*****

Pueblo, Co

illegal is a sick bird....
Nov 2nd, 2017 12:01 PM   Edit   Profile   Print Topic   Search Topic

The wiring schematic for the Fender WRHB's (this particular schematic) has 1 meg pots and it says 33 or 47 pf cap.

Can you school me on what the differences would be and how either one would affect the tone?

Pinetree
Moderator Emeritus
(with many stars)

NW Pennsylvania

Nov 2nd, 2017 12:09 PM   Edit   Profile   Print Topic   Search Topic

My preference is 47pf.


Here's a better explanation.

External link

Therealfrogman
Contributing Member
*****

Pueblo, Co

illegal is a sick bird....
Nov 2nd, 2017 01:15 PM   Edit   Profile   Print Topic   Search Topic

Thanks, Pinetree.

Mick Reid
Contributing Member
****

Australia

American-made in Oz!!
Nov 2nd, 2017 09:32 PM   Edit   Profile   Print Topic   Search Topic

Is it just me, or do the audio links not work???

When I click on one, it just directs back to the original page. Using latest Chrome.


edit: Just realised the above link is an archive site. Found the new location, audio works there!

(This message was last edited by Mick Reid at 11:44 PM, Nov 2nd, 2017)

Te 52

Laws of Physics

strictly enforced
Nov 2nd, 2017 10:03 PM   Edit   Profile   Print Topic   Search Topic

Here's a...

...link

DrKev

Paris, France

It's just a guitar, not rocket science.
Nov 3rd, 2017 08:45 AM   Edit   Profile   Print Topic   Search Topic

That's 0.047µF, or 47nF, and not 47pF, which is a factor of 1000 smaller than a tone cap and way to tiny for even a treble bleed capacitor.

I've always found .047µF too dark and I prefer 0.022µF. I don't see the point of having 1/2 of the range of my tone pots unusable to my ears.

Thanks for the link Te52!

ejm

usa

Nov 3rd, 2017 09:00 AM   Edit   Profile   Print Topic   Search Topic

Stop.
Need some clarification.

Do you have a link to the wiring diagram?
I did a brief internet search and nothing really convincing came up.

What are the caps used for?
Tone control?
Treble bypass/bleed on the volume control?

My gut tells me that regardless of the answers to any of the above questions, no matter where the caps are used, with those values you might not hear much difference, if any. I'd think that a tone control cap would be a little higher value, as would a treble bypass/bleed cap. But I have been wrong once or twice before in my life.

So.....
Are you sure that the values are 33pf and 47pf?
Or are they 0.033 uF and 0.047 uF?
(That would be 33,000 and 47,000 pf.)


Therealfrogman
Contributing Member
*****

Pueblo, Co

illegal is a sick bird....
Nov 3rd, 2017 09:40 AM   Edit   Profile   Print Topic   Search Topic

ejm, yes I am sure.

Te 52

Laws of Physics

strictly enforced
Nov 3rd, 2017 10:07 AM   Edit   Profile   Print Topic   Search Topic

OK, let's get this straightened out.

µ (micro) 10^-6
n (nano) 10^-9
p (pico) 10^-12

So .033µF = 33nF = 33,000pF

.033µF is a reasonable value for a tone cap. 33pF is not, it's way too small a value.

The caps discussed are for the tone control. The basic layout is, the output from the selector switch takes two paths: one goes through the volume control and to the jack, the other goes through the tone pot, then through the tone cap, then to ground.

DrKev

Paris, France

It's just a guitar, not rocket science.
Nov 3rd, 2017 10:14 AM   Edit   Profile   Print Topic   Search Topic

As I've said, even with 1 1Meg pot, 33pF or 47pF is way too small for a tone cap. Has to be a misprint.

Cal-Woody

USA/California

Why do I keep fixing things that work?
Nov 3rd, 2017 10:45 AM   Edit   Profile   Print Topic   Search Topic

So, getting back to the discussion on the capacitors used with the 1 meg ohm pots, these almost always bring out a very bright tone and would only use them if the pickups are dark sounding. As discussed above, the capacitors limit/tailor the amount of low frequencies allowed in once the tone control is turned down. If you have already installed these pots and like the way they sound, then your capacitor choices are the next step in finding the amount of low frequencies you want to adjust. For myself, I've have only tried them one time and they came with my Strat and Tele Custom Special pickups and found that they were way too bright for a single coil of any type,but have used them in a passive volume box that I wanted the most pass-thru on my guitar into the amplifier without muddying up my tone and have control over the different guitars being played through the same amp. I.E.: single coil VS humbucker volume differences.
But it may be just fine for your wide range pickups but have never had nor owned a guitar with them. You may probably end up with 500k or 330k pots to tame any extreme brightness.On a set of Gibson Burstbucker Pros, I found that they were very bright for a humbucker style of pickup and ended up using 330k pots with a .033uf orange drop cap, which really worked out nicely. So, keep in mind that you are adjusting/limiting the amount of low frequencies allowed while turning down your tone control and be listening for those desireable tones and this may help you with finding the right capacitor to compliment the performance you expect from your pickups.
Personally, I haven't heard much from anyone liking the 1 meg ohm pots on a guitar, but if they are really dark and woolly sounding, then it just might be the right combination for you.
Best regards, Woody

Therealfrogman
Contributing Member
*****

Pueblo, Co

illegal is a sick bird....
Nov 3rd, 2017 12:02 PM   Edit   Profile   Print Topic   Search Topic

Okay here is a pic of the schematic, sorry for any confusion. This info and discussion is very helpful to me.

Profile pic

Peegoo
Contributing Member
**********
**********
******

Enjoying

the downtime
Nov 3rd, 2017 12:07 PM   Edit   Profile   Print Topic   Search Topic

That is a misprint. It should be uf (microfarads), not picofarads.

Peegoo
Contributing Member
**********
**********
******

Enjoying

the downtime
Nov 3rd, 2017 12:19 PM   Edit   Profile   Print Topic   Search Topic

The general rules when it comes to pots and tone caps are:

1. For single coils (Strat, Tele, etc.), 250K pots and an .047uf tone cap.

2. For humbuckers (Les Paul, etc.), 500K pots and .022uf tone cap.

You can use 300K pots for pickups like P90s and Filtertrons. And you certainly can experiment with various combinations of pots and caps because the spec of each part does affect the tone of the pickups.

The critical component selection is to use an audio/log taper pot for the volume control. A linear taper pot will not work well because it rolls on and off too fast; it works more like an on/off switch than a volume control.

For a tone pot, it's up in the air: some players like the taper of an audio/log pot, and some prefer the linear taper pot.

Therealfrogman
Contributing Member
*****

Pueblo, Co

illegal is a sick bird....
Nov 3rd, 2017 02:30 PM   Edit   Profile   Print Topic   Search Topic

Okay, so the pots I ordered are the uf ones. I ordered a 47 and a 22. I think what is already in there is one or the other.

I am on a quest to see if I can make these pickups sound the way I want them without having them rewound. I love the guitar for what it is but I really love sc pups. I knew this thinline would sound sort of like the HB I have in my other tele and it does, it is a bit cleaner though. I am adding a link to a demo of some pups that were rewound to originl specs with the correct bobbins and almost correct pole pieces. Anyway I think this guitar in the demo sounds like what I want. If I do not get enough out of the pot upgrade I will probably get them rewound. Please do not tell my wife! She aint noticed this guitar aint been here before.....yet ;-)

BrandonWound WRHB's

Te 52

Laws of Physics

strictly enforced
Nov 3rd, 2017 04:08 PM   Edit   Profile   Print Topic   Search Topic

"...That is a misprint. It should be uf (microfarads), not picofarads..."

If you want to spec the cap in microfarads, it should read .033 µF. If you want to stick with whole numbers, it should be 33nF.

Cal-Woody

USA/California

Why do I keep fixing things that work?
Nov 3rd, 2017 05:17 PM   Edit   Profile   Print Topic   Search Topic

Well, I listened to the Brandonwound YT clip and the guitar sounded kinda on the bright side in all positions. Aside from the idea that they mod the pickups to have adjustable pole pieces, he never discussed the pots and caps used on his/their setup. So it kind of leaves you in the dark as to the entire setup and this left me feeling like, Is it better than the original design?
With not ever owning a guitar equipped with Wide Range Humbuckers, I have to wonder/assume that it is an upgrade but from what? He never gets into the entire discussion and kinda pissed me off to have listened to the entire clip and didn't really learn anything about the differences.
Question: is your guitar currently equipped with 1 meg ohm pots? If so, is it really bright like the one on the clip? Maybe it was just a poor recording and didn't emphasize anything that would make me interested in changing pickups.
Sorry but maybe your explaining how you are setup would give me/us s better determination of what it is you desire from your pickups.

Peegoo
Contributing Member
**********
**********
******

Enjoying

the downtime
Nov 3rd, 2017 05:26 PM   Edit   Profile   Print Topic   Search Topic

The WRHB pickup is a fairly hi-fi sounding unit. It's in the same family as the Guild Gold-tone humbucker: pretty bright for a humbucker, without the usual midrange hump that a lot of HB pickups have.

If you add a treble bypass mod to the volume control, you can get them to twang nicely too.

FunkyKikuchiyo

VT

Nov 4th, 2017 08:18 AM   Edit   Profile   Print Topic   Search Topic

A cap and a pot work together to alter the sound of the pickup in a manner that is a bit complex electronically, but can be simplified to please everyone except the most anal electrical engineers.

Think of the cap as the roll of point setter. It selects a frequency to start rolling down the tone. A .047uf cap rolls it off a bit lower and accents the midrange more than, say, a .022uf. For a pickup like a strat pickup it can add a nice, gnarly honk to the sound, but on a humbucker it is just too much, because it has more mids to begin with. I've taken out .047uf caps from humbucker guitars and had people thinking I changed the pickups, it can be that dramatic.

An important thing to remember is that they are interactive with the pickups, so "good" and "bad" can vary wildly.

On the .033uf, I like them on more modern style strats and teles, especially if the pickups are a bit on the underwound side.

In regards to pot value, it certainly gets more complicated than this, but just think of it as a distancer of the pickup to the cap. Turning the tone pot down all the way basically takes the resistance out, and is the same has hardwiring the cap with no pot. Turn it up and you're adding resistance, diminishing the effect of the cap. (again, these are layman's terms, and my apologies to any engineers for the distress it may cause you or your families).

I disagree strongly with one thing mentioned in the link:

"The capacitor only contributes to guitar’s tone when you lower the tone pot. If you always play with your tone pot wide open, none of this matters."

This is wrong. Well, it is correct if you're talking about a no-load tone pot. Remember what I said about the pot being the "barrier"... turned all the way up, the tone control has the resistance of the full value of the pot, 250k, 500k, whatever. The effect is small, but it is still there. Because the cap affects the pickup right in the frequencies where our hearing is most sensitive, (the human voice is "upper midrange", and we've evolved to tune into those pitches) these incredibly small effects are indeed audible. The classic example is the Strat bridge pickup. Wired with no tone control is brighter than wired with a tone control, even with the control on 10.

Also fun fact: you can minutely alter the sound of a circuit just by checking pot tolerances. If I replace the tone pot just for functionality on an instrument, I'll often find it change noticeably because the actual value went from 220k to 270k, both can be considered a "250k pot" but that extra 50k can make it a bit brighter and clearer.

Peegoo
Contributing Member
**********
**********
******

Enjoying

the downtime
Nov 4th, 2017 10:07 AM   Edit   Profile   Print Topic   Search Topic

Yeah, a cap (based on its spec) acts as an adjustable low-pass filter when used with a potentiometer As you roll off the tone control, the cap/pot progressively drain highs to ground, while retaining mids and lows in the signal that goes to the amp.

There are lots of ways to implement passive tone control in a guitar besides a pot & cap network. Add an inductor and you can turn it into an adjustable band pass filter, an adjustable midrange cut, a bass contour control (a la Reverend guitars), and more. Use two caps on either side of the pot and you can get a fairly good wah control as used by Roy Buchanan, Danny Gatton, and Bill Kirchin.

Next 20 Messages  

FDP Forum / Guitar Mods, Repairs, and Projects / 33 or 47pf capacitor




Reply to this Topic
Display my email address             Lost your password?
Your Message:
Link Address (URL):
Link Title:




Moderators: Chris Greene  Iron Man  reverendrob  

FDP, LLC Privacy Policy: Your real name, username, and email
are held in confidence and not disclosed to any third parties, sold, or
used for anything other than FDP Forum registration unless you specifically authorize disclosure.

Furtkamp.com 
Internet Application Development

Copyright © 1999-2017 Fender Discussion Page, LLC   All Rights Reserved