Tone caps values?

[devnulljp]

How do I tell the value of the capacitors on the tone controls of my guitar?
I've got a nice cheapie guitar but the electrics are awful...figured I might as well change out everything while I'm at it...
It's got double single-coil lipstick pu's if that makes any difference.
There are no values on the caps as far as I can see, nothing written on there.

[keeperofthegood]

Caps are notoriously inaccurate. The manufacturers say "20% tolerance" but it is well known they can be 50% out and even 100% out. Labeling them becomes a moot point when they could be 0.0022 or 0.0047 or any value between.

Otherwise, each manufacturer has its own choice of pots and caps. Together these make for filters that pass or block signal. What Fender uses passes a different pattern of frequencies than what Gibson does (for example).

So I am thinking that what would be the first place to start is by asking you what sound you are after? From that, then you can start looking at caps. Otherwise you would probably be hearing a lot from people on values, which wont help if it isn't towards the tone you want.

In the meantime, this is a fun program to play with:

http://www.duncanamps.com/tsc/index.html

What happens inside the guitar is pretty much the same, and this will give you some visual ideas to whats happening to your sound too.

[dwagar]

with single coils I would guess they used about .047uF, standard Fender spec.

You need a meter that measures capacitance to know what the originals are, but caps are pretty cheap to test a few different ones and find what you like.

[greco]

This topic has been discussed 100's of times on the Seymour Duncan forum (in case you want to have a look)

The most common values used are (all in UF's)
0.010, 0.015, 0.022, 0.030, 0.047

My ears are much too old to be able to tell that much of a difference, especially when the values are 0.005 UF's apart

The higher the value, the "darker" the pickup will sound when you roll back on the tone.

The debate rages on as to how much the cost and contruction (type) of cap influences tone. I don't want to go there. :sport-smiley-002:

I use mylar caps (they look like various sizes of "chicklets" gum). Not expensive.

Peace

Dave

[devnulljp]

Thanks for all the info. Not so much looking for ay particular tone...although 'chimey' comes to mind. Just ripping the cheapie wiring out of my cheapie Danelectro and figured I might as well replace everything. So I ordered a bunch of different caps to try em out -- not expensive (although I did find some expensive ones). I just wasn't sure where to start. So from what you guys have said I got a handful of values: 0.015, 0.022, 0.030, 0.047.

Thanks

EDIT: Anyone decipher this?

http://farm4.static.flickr.com/3164/2602062926_4c888b7d45_o.jpg

0.1 uF? 200V?
1uF 200V?
Type?

Know where I could get a couple?

[keeperofthegood]

Yes, I have read gobs of stories about how one make is better than another etc etc.

If you go googling around, you will find a lot of 'experimenters' out there. One fellow had I believe a 10 or 12 position switch for capacitors, and 2 switches for coil selection. Just keep it in mind, the accuracy with with capacitors are made can be really poor. 100% off on a 0.022 is 0.044 or 0.011

As to the pic, MFD is the old style way of saying uF, so 0.1 uF and I honestly forget off the top of my head if its metallized polyester or paper inside that style, but I would lean towards paper.

The other that you may encounter too is MMFD or uuF, micro micro farad

http://www.justradios.com/MFMMFD.html

[Geek]

And to confuse matters, more and more technical publications (including my own) are going standardized with nanofarad for values between 1000pF and 1uF, so your list there, 0.010uF, 0.015uF, 0.022uF, 0.030uF, 0.047uF can also be written on schematics (and capacitors) as 10n, 15n, 22n, 30n and 47n :wink:

(heh, personally I found out this is good, since my old eyes can no longer see the "dot" printed on caps anymore. So what is written 0.047uF I see as 0047uF :frown: )

Cheers!

[greco]

0.1 uF? 200V?
Type?

Know where I could get a couple?

Did you want these for your guitar? (I assume)

The pic is a bit small, but I'm going to guess that it is an axial electrolytic cap. A cap of 200 V max is elephant size overkill. The voltages in a guitar are in millivolts (at a guess...someone please correct me if I'm wrong on any of the above :bow:)

.1 uF (MFD) is also really going to hit your highs hard. 0.047 is often used in bass guitars.

Still want the 0.1 uF caps? If you do, I could look and mail you couple, IF I happen to have that value. They won't be rated for 200V though.

Dave

[keeperofthegood]

And to confuse matters, more and more technical publications (including my own) are going standardized with nanofarad for values between 1000pF and 1uF, so your list there, 0.010uF, 0.015uF, 0.022uF, 0.030uF, 0.047uF can also be written on schematics (and capacitors) as 10n, 15n, 22n, 30n and 47n :wink:

(heh, personally I found out this is good, since my old eyes can no longer see the "dot" printed on caps anymore. So what is written 0.047uF I see as 0047uF :frown: )

Cheers!

>__> I have to use a magnifier to read the printing on transistors now...
:) I like the use of n too, not for the decimals but when I see 1000 and 10000 and 1000000 I lose track of how many zeros there are!


AND!! It too me a bit of google time however:

http://www.soundchamberrepairs.com/caps.htm

I reallise this doesn't get you the materials necessarily, but it is a step closer.

[mhammer]

I use a bi-directional tone pot. This involves a 1M linear tone pot where the wiper connects to the volume pot input, and the two outside lugs each connect to ground through a different-value cap; .0068 and .022uf are commonly selected values. The one provides the usual muting function more suitable to the neck pickup and the other provides gentler "rounding" more suitable to the bridge pickup. Turn the pot one way and you get the one function. Turn it the other way and you get the other one. Set it to the middle and you have two 500k pots set to minimum treble cut.

One of the things I like about it is that each side takes the full range and compresses it to only half the required rotation. If you're a fan of "pinky wah" a la Danny Gatton, this will let you do it more easily.

Although cap tolerances are difficult to make as tight as those of resistors, they are not quite as bad as keeperofthegood depicts, although that assumes they are new. I find the tightness of the tolerances tends to be worst for very small values (i.e., under 470pf) and larger values (>22uf), neither of which are germane to guitar tone controls.

Some folks make a big deal out of bumble-bee and other caps. Frankly I have a hard time seeing merit in it. They're only for bleeding treble to ground. Caps matter more when they are in series, and when one is passing a multi-source signal with lots of bandwidth (i.e., a keyboard or a mix-down). In those instances the properties of the caps can play a significant role in the alignment of harmonics and the "definition" of the resulting sound. Guitar notes from a humbucker aren't in the same league as far as I'm concerned, and if you play through a distortion of any kind, the amount of intermodulation occurring in the pedal/circuit is such that whatever definition might theoretically be preserved at the guitar via pickiness over caps is lost at the pedal.

I suspect those who make a big deal out of cap type likely have tone pots whose value is too small to prevent unwanted bleed-off; perhaps even because they seek the degree of comfortable adjustment found in the bi-directional pot I describe. In truth, you can use pretty much ANY tone pot value you want IF it is a able to provide a "zero ohms" or zero load setting at one end and effectively lift the connection between volume and tone pot. You can do that by gently prying apart the tabs that hold the pot casing in place and painting one end of the resistive strip with a thin coat of durable lacquer of some type that insulates the wiper from the strip.

[keeperofthegood]

:) Indeed Mark, my experiences have been in college when I got to watch so many of my lab experiments poof on me >.< and with old radio's. NOS caps are fearsome! I say! (but visually needed in some restorations, stuffing new in old is not always a possibility) but even at 20% (the usual value on new) that is still a fair bit of play in the values.

I like the tone control you described too actually, had that at the back of my mind to try. I think I am going to rout through some of my parts boxes and see what I have to mess with too XD

[greco]

Did you want these for your guitar? (I assume)

The pic is a bit small, but I'm going to guess that it is an axial electrolytic cap. A cap of 200 V max is elephant size overkill. The voltages in a guitar are in millivolts (at a guess...someone please correct me if I'm wrong on any of the above :bow:)

.1 uF (MFD) is also really going to hit your highs hard. 0.047 is often used in bass guitars.

Still want the 0.1 uF caps? If you do, I could look and mail you couple, IF I happen to have that value. They won't be rated for 200V though.

Dave

I just have to know, from all you electronics gurus, am I reasonable/close with the above information?

Waiting in suspense:bow:

Dave

[mhammer]

Keep in mind that the tone control always provides a path for treble to bleed off to ground, even when set to full treble. How much and which treble bleeds off will depend on the value of the pot, and the value of the cap. With a cap value of .1uf, that pot would have to be some big (e.g., 1M or more) to avoid losing any treble even when set to full treble. Smaller cap values permit use of smaller pot values without sacrificing too much top end.

Is .047uf suitable for bass? Perhaps. Certainly at max treble cut, it won't muffle the bass as much as it would muffle a guitar. The question is whether that value, plus the pot value, would permit enough brightness at the max treble setting. If it was an EB-0 with a big old humbucker, I'd say yer fine. If it was a Rickenbacker, maybe not so much.

Do note that caps in series result in a smaller effective value, working somewhat the same way that resistors do in parallel. So, two .1uf caps in series is equal to .05uf. A .1uf and .033uf in series will yield an effective capacitance value of .0319. I mention this because you may have a combination of values that can nail a suitable choice.

[greco]

Do note that caps in series result in a smaller effective value, working somewhat the same way that resistors do in parallel. So, two .1uf caps in series is equal to .05uf. A .1uf and .033uf in series will yield an effective capacitance value of .0319. I mention this because you may have a combination of values that can nail a suitable choice.

Thanks mhammer...good thing to remember if one doesn't have the "exact" value of cap on hand.

Dave

[devnulljp]

Wow, this is all great info - we have a bunch of knowledgable people here. Thanks.
FWIW, the pots are high values: 1meg/100K stacked ike this:
http://www.danguitars.com/images/Img1022.gif
I've got some parts on order, a bunch of different caps, so I'll see how it goes. Found an intersting article here about trying different caps values, which I might try: http://www.premierguitar.com/Magazine/Issue/2008/Mar/Auditioning_Tone_Capacitors.aspx
That switch is still giving me a headache though.

[greco]

Good article

Please keep us posted on your project and cap experiment findings.

Dave

[konasexone]

Try this simple recipe : Fc is the corner frequency, where you want your highs to start rolling off. In fact at Fc they already have to 70.7 % of their original.

R will be the value of the pot used in ohms

C will be the value of the cap used in Farads

Fc = 1 / (2 x 3.14 x R xC)

if you want C then C = 1 / (2 x 3.14 x R x Fc)


So lets say your pot is 500kohms, and the corner frequency you desire is 2 khz

then the cap you would use is


C = 1/ (2 x 3.14 x 500 000 x 2000) = .159 nF = 159 pF

The closest standard value would likely be 150 pF.:wave:

[greco]

Try this simple recipe : Fc is the corner frequency, where you want your highs to start rolling off. In fact at Fc they already have to 70.7 % of their original.

R will be the value of the pot used in ohms

C will be the value of the cap used in Farads

Fc = 1 / (2 x 3.14 x R xC)

if you want C then C = 1 / (2 x 3.14 x R x Fc)


So lets say your pot is 500kohms, and the corner frequency you desire is 2 khz

then the cap you would use is


C = 1/ (2 x 3.14 x 500 000 x 2000) = .159 nF = 159 pF

The closest standard value would likely be 150 pF.:wave:

This is cool !! Thanks

What would be some of the typical/reasonable corner frequencies you would suggest for various styles of playing and or types of guitars/pickups? (I'm assuming that 2khz is just an example for the purpose of the math)

Thanks

Dave

[konasexone]

I like 500K pots for volume and tone in my Les Pauls. A 22 nF - 47 nF cap usually does the trick. (.022 uF - .047uF).

[Ripper]

Depending on the pickup being used, sometimes I use a .01uf for the neck pickup on my les pauls.

[konasexone]

Yup I could see that for an exceptionally bright pickup. Its all up to your ears in the end, there's no perfect value.