Treble Bleed Cap Mod

[rubalup]

Anybody has done this mod?

I´m waiting for my Dimarzio 36th with covers to replace the stock pu´s on my ZM SE...so maybe that will solve the problem, but in the mean time I´m thinking in doing this mod to avoid the muddier sound I´m getting specially when rolling the volume off on the neck pu.

So, I really want to hear your thoughts and experiences.


http://www.ratcliffe.co.za/articles/volumepot2.shtml

 

[Agileguy]

I do it on all of my guitars. I hate getting mud when I roll the volume back. It works fantastically for me.

 

[John Beef]

I do it on all of my guitars. I hate getting mud when I roll the volume back. It works fantastically for me.

+1. Though, I did a guitar once with the cap/resistor in series like in the article (can't remember the values offhand) and it did make the guitar brighter as I rolled off the volume. IMHO, PRS has it right, 180pf cap, no resistor.

 

[Agileguy]

I personally like that it gets a tad brighter with the resistor. It helps me cut a bit more with less gain. Or you can think about it as making the tone with the volume on full a bit warmer.

 

[garrettb]

Does the Zach Myers not already have one? PRS guitars, including SE models, usually have a 180pf cap on the volume control. That's a very conservative value for a treble bypass cap though, so you may want to try 330pf or 680pf. Different pickups interact differently with the volume control, so it may take a little experimenting to find the right cap and resistor (if you even use one) values.

 

[rubalup]

I feel embarrassed... Truth is that I haven't even look at the control cavity. I just assumed it didn't have any


Edit: I just checked and my ZM don't have a treble bleed cap. My Santana does have a 180pF cap and it performs great maintaining presence when rolling the volume down.

 

[rubalup]

Does the Zach Myers not already have one? PRS guitars, including SE models, usually have a 180pf cap on the volume control. That's a very conservative value for a treble bypass cap though, so you may want to try 330pf or 680pf. Different pickups interact differently with the volume control, so it may take a little experimenting to find the right cap and resistor (if you even use one) values.

Thanks a lot for your info Garret. I checked and my Santana SE has a 180pF cap, but the ZM has not.

I have a 470pF cap laying around... do you think it could work? I would prefer to use the 180pF but couldn´t find any... would the difference be to much? I really dont know much (read anything) about electronics other than being semi-handy with a soldering iron.

 

[László]

Thanks a lot for your info Garret. I checked and my Santana SE has a 180pF cap, but the ZM has not.

I have a 470pF cap laying around... do you think it could work? I would prefer to use the 180pF but couldn´t find any... would the difference be to much? I really dont know much (read anything) about electronics other than being semi-handy with a soldering iron.

A cap like this is a highpass filter. Higher values will raise the cutoff frequency of the highpass filter.

Think of it this way:

Lowpass filter: You're Indiana Jones in the movie where he's going after the holy grail. "The penitent man kneels" to avoid the blade weapon that's chest-high. That's a lowpass filter. The cutoff point is where the blade whirls, and everything over that point is, well, cut off. If he doesn't duck, Indy's head isn't part of Indy any more. The high frequencies are cut off.

Highpass filter: A highpass filter is the opposite. With a highpass filter everything above the cutoff point passes through the filter. In that case, everything below the cutoff point is cut off. Indy loses his legs and feet. The bass is cut off.

Increasing the value of the cap means that as you roll back the volume, you get less bass.

Stuff like this is a balancing act between losing bass and losing treble. A tradeoff of what can be done without.

 

[rubalup]

A cap like this is a highpass filter. Higher values will raise the cutoff frequency of the highpass filter.

Think of it this way:

Lowpass filter: You're Indiana Jones in the movie where he's going after the holy grail. "The penitent man kneels" to avoid the blade weapon that's chest-high. That's a lowpass filter. The cutoff point is where the blade whirls, and everything over that point is, well, cut off. If he doesn't duck, Indy's head isn't part of Indy any more. The high frequencies are cut off.

Highpass filter: A highpass filter is the opposite. With a highpass filter everything above the cutoff point passes through the filter. In that case, everything below the cutoff point is cut off. Indy loses his legs and feet. The bass is cut off.

Increasing the value of the cap means that as you roll back the volume, you get less bass.

Stuff like this is a balancing act between losing bass and losing treble. A tradeoff of what can be done without.

LOL very nice explanation!!

so I have a 100pF and a 470pF cap... wich one would be "safer"?

 

[László]

LOL very nice explanation!!

so I have a 100pF and a 470pF cap... wich one would be "safer"?

I it were my guitar, I'd probably just buy a 180 like PRS uses stock, or go with a 220. They cost next to nothing.

But that's just me.

 

[rubalup]

Thanks LSchefman, I´ll try to find a 180pF, but on two places I´ve been I couldn´t find any of those values.


this is PRS tech team response about the absence of a treble bleed cap on the ZM model:


"Thank you for writing PRS Guitars. Many of our Singlecut models do not use the cap on the volume pot. This was a spec that Zach wanted on his signature model to get a darker tone on rolloff.

I hope you find this information helpful. Thank you for your continued support of PRS Guitars."

 

[garrettb]

Right. The 470pf will work fine, it'll just be a little brighter than the 180pf as you turn down the volume. It takes a little experimenting to find the right value so Indiana doesn't lose his head.

An alternative to the treble bypass cap is to change the wiring to what's usually called "50's wiring" based on old Les Pauls. It just involves moving the the tone control connection from the outside lug of the volume (input) to the middle lug (output). This causes the tone controls to work a little differently (less effective in the upper numbers), but without their load on the volume controls, the pickups won't get so dark sounding when you turn down.

The great thing about these tweaks is they don't cost much and are easy to reverse, as long as you know how to solder!

 

[László]

Thanks LSchefman, I´ll try to find a 180pF, but on two places I´ve been I couldn´t find any of those values.

Stew mac has them, $3.49 for 10 caps, and I think these are right, since they say the 180s are for "PRS Treble Bleed" right on the page, but I'd call them to verify if you're not 100% sure:

http://www.stewmac.com/Pickups_and_...ts/Capacitors_and_Resistors/Ceramic_Caps.html

Hard to find a cheaper mod!

 

[rubalup]

Stew mac has them, $3.49 for 10 caps, and I think these are right, since they say the 180s are for "PRS Treble Bleed" right on the page, but I'd call them to verify if you're not 100% sure:

http://www.stewmac.com/Pickups_and_...ts/Capacitors_and_Resistors/Ceramic_Caps.html

Hard to find a cheaper mod!

Thanks a lot... I will try to find them locally. The shipping cost to my country is way to high to just order some caps... and tbh I already have a box full of stewmac pots, wires, etc so I cant justify ordering anything :bawling:

I ask the tech team of PRS and here´s their answer about the 470pF:

"A 470 would be too high. You should be able to source a 180 online through someone like mouser.com, amazon.com or wdmusic.com.

Regards"


Thanks to all that chimed in... great info.

 

[BrianC]

PRS has it right, 180pf cap, no resistor.

THIS!!!

 

[rubalup]

THIS!!!

I´ll try it this weekend... I finally culd get a 180pF cap.

Last night I installed the 470pF but it was indeed to much... I liked how it worked with the volume on the 7-9 settings... but lower than that I losed all my "balls" and the sound was to trebly. 15 minutes after I was clipping that cap off

 

[László]

I´ll try it this weekend... I finally culd get a 180pF cap.

Last night I installed the 470pF but it was indeed to much... I liked how it worked with the volume on the 7-9 settings... but lower than that I losed all my "balls" and the sound was to trebly. 15 minutes after I was clipping that cap off

That result is more or less what I expected...Indy's feet and lower legs were cut off!

The 180 should get you there without a hitch. Indy will only lose the soles of his shoes.

 

[rubalup]

That result is more or less what I expected...Indy's feet and lower legs were cut off!

The 180 should get you there without a hitch. Indy will only lose the soles of his shoes.

I just did the mod with the 180pF...

As usual PRS got it right!

 

[Roland Polyak]

What a great Christmas day: I've just installed a treble bleed kit to my PRS McCarty 594!

 

[Roland Polyak]

After a lot of research I've chosen 1 x Sprague Orange Drop Capacitor – 0.001 uf 1 x pre-soldered 130k resistor.