Ever notice that when you roll your guitar's volume down, the tone gets really muddy and flabby? There's a reason for this.
The Science of it all:
Electricity only does one thing: search for ground. Yes we manipulate it and make it do things on its way there, but all that cool stuff happens while the electrons are searching for ground. When you turn your guitar's volume down, you're allowing some of the current to go to ground as opposed to going out to the amp to make sound. (Think of it like a valve that diverts water's flow when you turn it......) When you do this, the frequencies that leave first are the high ones, which makes the tone seem muddy and thick, without the "edge" on it.
A way to avoid this is by using what's called a treble bleed circuit. It's called this because it prevents the treble frequencies from bleeding off. It allows some of the treble frequencies (the ones we want to keep) to walk around the volume pot to the output, rather than go through it and get lost to ground.
Some folks just use a capacitor for it, some folks use a capacitor and a resistor in series, some folks use a cap and a resistor in parallel. Obviously, it's up to you and your ears how you want to do yours. I've got two guitars now that come to mind with two different treble bleed circuits in them and both sound great.
You'll probably have to mess with the values a bit to just get it right. If your circuit is too aggressive, then it will sound really thin when you get the volume down way low. Obviously, if it's not aggressive enough, you'll know because it's still too dark.
How to do it:
Put the circuit across your volume pot on the two terminals that AREN'T grounded. Whether you use a cap alone or a cap/resistor combo, this is where it goes. Here's something I recommend for your first time:
My Treble Bleed Circuits:
On my ES-333's neck pickup, I just used a cap alone. It's 560pf (0.00056uF). It's not too aggressive, but it does have a noticeable effect. I didn't bother to put one on the bridge pickup because you don't really need it. That one stays bright enough.
On my Les Paul Classic, I put in just a 560pf cap on the neck pickup like before, but it got too thin. It sounded great until you got down to about 6 or so, and then it sounded really unnatural. So then I put a 220k Ohm resistor in parallel with the cap and it got a lot better. However, I found that I still didn't really like it all the way down the dial, so I wanted it to be switchable. I have the pots that I want in this guitar and didn't want to replace one with a DPDT push/pull or similar.
So I went to Radioshack and I got this tiny little toggle switch for like $3 with the intent of mounting it on the underside of the pickguard with just enough of the arm hanging out to grab.
I took the bridge pickup out of the ring and used a Dremel to cut some small notches in the underside that will be hidden by the pickguard. The wires then can run down into the pickup cavity and back through to the main electronics cavity. I then superglued the switch to the underside of the pickguard. (Locate it with tape first and make sure you know exactly where you want it.) Put one end of your circuit on the pot. Splice the other end on to a piece of your wire and run the other end of it out to your switch. Then run the return line from your switch back to the second terminal of the pot.
Here's some photos of it. I think it came out great. I didn't do any permanent mods to the guitar, and the pickup ring and/or the guard can be easily replaced. No new holes, etc. and it's pretty discreet. Yeah you can see it, but it's not really obvious.
This page was last updated 02/15/10