The Capacitor (?) on a volume pot.

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Slowy
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The Capacitor (?) on a volume pot.

Post by Slowy »

I moved the thingy from my old pot to the new one.
Questions:
What does it do?
Do I need it?
Would a better one make a difference?
What is a better one?
Where do I get one?

500K pot. No tone knob.
volcap.JPG
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Re: The Capacitor (?) on a volume pot.

Post by Starfire »

Treble bleed, innit? Basically, it stops the mud when you roll the volume back.

An article:
https://www.fender.com/articles/tech-ta ... -your-tone

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Re: The Capacitor (?) on a volume pot.

Post by Jay »

You should add a resistor!

And here is a more sophisticated one...

https://www.amplifiedparts.com/products ... eble-bleed
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Re: The Capacitor (?) on a volume pot.

Post by sizzlingbadger »

Probably better off removing it on that PRS.
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Re: The Capacitor (?) on a volume pot.

Post by JustMatt »

It is a rudimentary treble bleed.

Adding a 220k(ish) resistor will smooth out the taper of the volume control.

Removing it completely will increase treble loss when you roll off the volume, which could be useful if you dont have a dedicated tone control, or not if you just like the volume to control the volume.

A more expensive cap wont make a difference, a different value cap may.

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Re: The Capacitor (?) on a volume pot.

Post by Single coil »

Dude at the local shop didn't have any caps in uF, so he gave me these massive fucking things out of god knows what. 440k somethings. Stuck them in the goldtop.
Roll the tones right back and it sounds like I'm poppin and slappin like no ones business.
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Re: The Capacitor (?) on a volume pot.

Post by Slowy »

ToneLoungeMatt wrote:It is a rudimentary treble bleed.

Adding a 220k(ish) resistor will smooth out the taper of the volume control.

Removing it completely will increase treble loss when you roll off the volume, which could be useful if you dont have a dedicated tone control, or not if you just like the volume to control the volume.

A more expensive cap wont make a difference, a different value cap may.
From full power/volume I get an instant change with the slightest movement of the knob. It sucks out the mids and provides a somewhat meek sounding clean tone. Not bad, but certainly not sparkling.

Is it a cap or a resistor?
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Re: The Capacitor (?) on a volume pot.

Post by Slowy »

sizzlingbadger wrote:Probably better off removing it on that PRS.
OK. Why?
I ask because you know these beasties.
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Re: The Capacitor (?) on a volume pot.

Post by Single coil »

That little blighter looks more like a capacitor than a resistor.
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Re: The Capacitor (?) on a volume pot.

Post by Starfire »

That's a capacitor but some treble bleed circuits have a capacitor and a resistor. What you could do is make a couple of iterations of treble-bleed circuit (one with resistor, one witout, etc.) and attach them to aligator clips so you can swap them in and out and see (or, rather, hear) which you like best.

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Re: The Capacitor (?) on a volume pot.

Post by sizzlingbadger »

There is no tone control so allowing the top end to roll off a bit when you roll the vol back is pretty useful. I also found that it got very thin when you rolled the vol back with the cap in place.
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Re: The Capacitor (?) on a volume pot.

Post by Slowy »

sizzlingbadger wrote:There is no tone control so allowing the top end to roll off a bit when you roll the vol back is pretty useful. I also found that it got very thin when you rolled the vol back with the cap in place.
One thing the Lollar does is demonstrate how thin and shrill the original pickup is. It now has fat mids with a pleasing but not overly bright top end.
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Re: The Capacitor (?) on a volume pot.

Post by tubeswell »

Treble bypass or 'bright' cap. It allows high frequencies to bypass the resistance between the pot input and the pot wiper when the pot rotation is anything less than full.* The amount of capacitance of the cap determines the amount of high frequency bandwidth in the bypass frequencies. More capacitance means more mids (as well as highs) get through. It is common to see 500pF to 1nF in this situation and even as much as 10nF (.01uF) or 22nF (0.022uF). The amount of bandwidth that gets bypassed also depends on the overall resistance of the pot and whereabouts on the pot rotation the pot wiper is situated. With the pot at full rotation, the bypass cap has no effect (because the pot wiper is in direct contact with the pot input and the cap is therefore completely shorted out of the circuit).

*The resistance between the pot input and the pot wiper (that exists when the pot is not at full rotation) effectively become series resistance in the signal path, which would otherwise tend to roll-off high frequencies.
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