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hey all
i have a tokai es 335 copy with only 1 vol and 1 tone and a 3 way switch. i'm replacing the stock gotoh pickups with some handwound highorder pickups. my question is i have some wiring diagrams showing a .047 cap on the tone pot and another diagram showing .022. what is the difference in sound and what do these caps do? anyone have any recommendations?
 

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hey all
i have a tokai es 335 copy with only 1 vol and 1 tone and a 3 way switch. i'm replacing the stock gotoh pickups with some handwound highorder pickups. my question is i have some wiring diagrams showing a .047 cap on the tone pot and another diagram showing .022. what is the difference in sound and what do these caps do? anyone have any recommendations?
You likely won't hear a super big difference but there will be some.

Capacitors pass high frequencies better than lower ones. You can think of them as AC signal voltage resistors that have a sliding value. At very high frequencies they have a very low resistance value. As you slide down in frequency the "resistance" value will go up. At low bass frequencies that tone cap is a BIG "resistor".

With AC voltage like a signal, capacitors and inductors show this property which is called "reactance", or AC resistance if you like.

Tone controls in amps and guitars take advantage of reactance to allow you to adjust the tone of the device. In your guitar they hang a cap from the signal line to ground. The cap will leak treble to ground but lower notes will be less affected so it will sound like the treble has been reduced. The tone pot is just a real resistance in series with the tone cap so you can adjust how deep the tone cut will be.

The value of the cap determines the midpoint of that sliding reactance range. This means the action will start happening at a different point.

Think of a graphic EQ with sliders. You're feeding it with a full range signal, like classical music or Moody Blues where you have everything from the lowest bass to the highest tweets. You leave the first few slider cuts alone but once you get into the midrange you start to pull the sliders down, each one a bit more than the last until the final two sliders are at the very bottom.

This is what its like putting a tone cap into your guitar! If the above example was a model of a .02 mfd cap then if you changed it to a bigger value like .047 then it would be like shifting that curve of slider pots down a slider or two, so that the cut started happening earlier and killed treble even faster.

The tone pot would act like changing how deep the sliders would be cut. Still the same curve but the cuts would not be as deep.

So the short answer is that a larger value tone cap would cut the treble earlier and deeper.

Which one should you go with? Try 'em both and go with what you like! If you want to stay stock you might look to see if when they changed the cap value they also changed the resistance value of the tone control. The two parts work together. If you see that the .02 cap goes with a 250k pot and the .047 cap uses a 500k then you might want to stay consistent.

Hope this helps!
:food-smiley-004:
 

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There you have it, well said Wild Bill... I have also found that the type of cap will effect that curve. Some caps roll everything off in a range others seem to have a more linear roll off, based on using linear pots. I have tried many different types and found they have some different characteristics, not really any tone magic just smoother range. IMO I have found paper in oil type to be one of the smoothest, the vitamin Q or T style. By the way I have set of Highorder pups and they are awesome. Had them wound for my Epi Sheraton, told Jeff to think of Dickey Betts big red 335 and he came in on the money....
 

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That explains why I like the .047 better.
 

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I remember years ago they used to say .047 for single coils and .022 for humbuckers, but like Bill said it's all about what you want for tone/sound.
I've seen lots of les pauls with a .022 on the bridge and a .01 on the neck. My oneflying v uses a .033. I've also heard of guys really playing around and going with .1 caps. They are easy to change so try them out and see what sounds best for you.

Bill made a good point about the pot size too, usually the bigger the cap the bigger the pot.
 

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Hi!

Sorry to flog a dead horse (or thread) but I was swapping out a pickup in my Godin SD yesterday and I remembered having read this thread and only mildly understanding it!! Here's my problem:

My Godin SD is a H-S-S setup with a master volume and master tone and a 5-position selector switch. Positions 2 and 4 (the phased positions) are kinda muddy while positions 1, 3 and 5 are clear. Now I expect this to happen but would really like to have this a little clearer sounding.

If I changed the value of the cap would this happen? I wouldn't mind rolling off the treble in positions 1, 3 and 5 if necessary.

I don't remember the value of the pots but I think they were 250K and the cap is a .033 uf. My guess is that is somewhat of a compromise seeing as there are both single coils and a humbucker in this guitar.

Any insight would be greatly appreciated!
 

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the 250K pot is going to cut some of the highs too. Great for getting rid of the ice pick.

If you're in the muddy zone, first I'd try dropping and adjusting the pickups.
Then I'd try a 500K pot.

A .022 might help get that humbucker out of the mud, easy to try.
 

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...
My Godin SD is a H-S-S setup with a master volume and master tone and a 5-position selector switch. Positions 2 and 4 (the phased positions) are kinda muddy while positions 1, 3 and 5 are clear. Now I expect this to happen but would really like to have this a little clearer sounding.

If I changed the value of the cap would this happen? I wouldn't mind rolling off the treble in positions 1, 3 and 5 if necessary.
...
The standard tone control on a guitar is a low pass filter, which simply means that it attenuates the higer frequencies based on the values of the RC filter. If your guitar is muddy, attenuating the higher frequencies will only make it muddier.

You might want to consider re-working the tone pot into a high pass filter, which would allow you to roll of the low end as the tone pot is turned down.

This little modification will cost the same as changing the cap, but if you want to keep the low pass filter in tact I would recomend a switching pot. This will allow you to have either-or, or you may also try running the circuits in parallel or series.
 

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You might want to consider re-working the tone pot into a high pass filter, which would allow you to roll of the low end as the tone pot is turned down.

This little modification will cost the same as changing the cap, but if you want to keep the low pass filter in tact I would recomend a switching pot. This will allow you to have either-or, or you may also try running the circuits in parallel or series.
This sounds interesting. Could you please explain the actual wiring in more detail (with and without the switching pot).
Also, who supplies switching pots?

Thanks. No hijack intended here.

Dave
 

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A treble bleeding cap (across the volume control) is another way to clean up some mud, especially if it's happening at lowered volume.

I'm very curious to see the schematic this high pass filter idea as well.
 

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This sounds interesting. Could you please explain the actual wiring in more detail (with and without the switching pot).
Also, who supplies switching pots?

Thanks. No hijack intended here.

Dave

Here is a page that explains the two simple circuits and they even have a calculator as well.

http://www.muzique.com/schem/filter.htm

If you want to use a switching pot so that you can keep the current stock controll and add a high pass then you need a dual pot with a dpdt switch (the switch is standard, but they are hard to find with a dual pot, so you might have to go with a dual pot and a dpdt switch). So the 'easiest' way to keep the guitar looking stock would be to change the volume pot to one that has the dpdt switch and use a dual pot for the tone control. This will avoid drilling any holes in the guitar to add the extra switch, but you will be pulling up on the volume control to switch the function of the tone control.

If you run the circuits in series using a ganged pot, you will end up with just the midrange when you roll off as both the high and low end would be rolling off at the same rate.

Here are some pretty piuctures using a 250K pot and a 4.7nf cap for the low pass and a 47nf for the high pass the pot is turned down by 90% in the simulations.

the LPF:



the HPF:


The two circuits in series (sharing on ganged 250k pot):


and the same thing in parallel:



Putting the circuits in series or parallel causes the filter components to interact, so they don't allways behave as you might expect them to. With two seperate tone pots you can get some pretty strange results.

You can get switching pots at any music store of from WD or allparts. Dual pots with the switch are much harder to find, probably because they are quite large (WD & Allparts don't have them). I've gotten them from double H in Toronto a while back.
 

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Here is a page that explains the two simple circuits and they even have a calculator as well.

http://www.muzique.com/schem/filter.htm
Sorry, you lost me there. Those diagrams used fixed resistor values.

The tone circuit in a guitar uses the pot like a voltage divider, right? Part of the signal goes straight on toward the output, the rest is shunted through the cap to ground, and those proportions (how much each way) are controlled by the pot. At least that's how I figured it worked, just looking at how it's wired.

So how would the high pass filter look?
 

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Sorry, you lost me there. Those diagrams used fixed resistor values.

The tone circuit in a guitar uses the pot like a voltage divider, right? Part of the signal goes straight on toward the output, the rest is shunted through the cap to ground, and those proportions (how much each way) are controlled by the pot. At least that's how I figured it worked, just looking at how it's wired.

So how would the high pass filter look?
Your volume pot is wired that way, but your tone pot has one unsoldered lug and is just a variable resistor with the cap wired from the other lug to ground. The tone pot is wired in parallel with the pickup and provide high frequencies a path to ground at the amount allowed by the resistance (ie more resistance means less high end is thrown away). Since we don't have infinate resistance, there are always some high frequencies bled to ground using this system (allthough the amount that 250K ohms throws away is very small and nothing to worry about)

The variable high and low pass filters would be wired in series with the output of your volume control (the IN shown in the diagram) with the junction between the resistor and the cap being your output.

with a .047uf cap, a 100K ohm pot (with a 2Kohm resisor in series for a high pass to prevent a short to ground) would give you a variance between 33hz and 1.7Khz. You may want to use a 1Mohm pot (with a 10Kohm resistor in series to ground) and a .0047uf cap giving you a 33hz to 3.4Khz variance.

Look for a schematic for a fender TBX control - that will also give you both the high and low pass filters in one dual ganged pot with a center detent.
 

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You may be right, but I would expect it to be wired like this:


As this keeps the tone pot out of the signal path (it's a shunt filter - it provides a variable resistance for high frequencies to ground).

Passive high pass filters are not seen very often in guitars as they put a cap in series with the signal (as the circuits that I had noted) and a basic lpf shunt circuit (which would pass low frequencies to ground) would typically require an inductor which would be physically large to be effective for passing low frequency audio.

If you want to try building one of the HPF's like the example I listed, you can put it anywhere in line with the guitar (i.e. in a box that you can plug the guitar into). This allows for easy experimentation and requires no modification to the guitar in case it turns out to be not to your liking.
 
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