DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: Alpha579 on June 03, 2004, 05:33:10 PM

Title: brighten tone as volume pot on guitar reduced?
Post by: Alpha579 on June 03, 2004, 05:33:10 PM
Is it possible, without using an inductor, when series resistance is added to an overdrive circuit when the volume control is turned down, create a low cut filter? you could do it with an inductor like this i think:

resistance from guitar pot
   |
--/\/\/----------------(to rest of circuit)
              |
              &
              &  (inductor)
              &
              |
             grnd

Can you do this without an inductor?
Title: brighten tone as volume pot on guitar reduced?
Post by: Alpha579 on June 03, 2004, 05:37:51 PM
ah, sorry, diagram didnt come out like i expected :oops: . Its just a resistor, then an inductor to ground
Title: brighten tone as volume pot on guitar reduced?
Post by: cd on June 03, 2004, 05:41:48 PM
You want to add highs when your guitar's volume is turned down?  Have you tried a cap across the volume control - that usually works very well, like a bright switch.
Title: brighten tone as volume pot on guitar reduced?
Post by: Alpha579 on June 03, 2004, 06:12:38 PM
yeh, i might do that to my guitar, but i want to be able to use this pedal wiv lots of guitars without modding them all...
Title: Not the Same
Post by: petemoore on June 03, 2004, 08:25:57 PM
I'm gonna put a small cap across my favorite pickups's volume controls, I'M P.D.Sure I'll like it better that way.
 For the vol control to do this the cap has to be on it as far as I know, otherwise a treble boost could be used to accentuate treble of any 'incoming signal.
Title: Re: Not the Same
Post by: cd on June 03, 2004, 08:36:37 PM
Quote from: petemooreI'm gonna put a small cap across my favorite pickups's volume controls, I'M P.D.Sure I'll like it better that way.
 For the vol control to do this the cap has to be on it as far as I know, otherwise a treble boost could be used to accentuate treble of any 'incoming signal.

Huh?  Just put a cap between the "in" and "out" lugs of your volume pot.  The way it works is at high frequencies, the cap looks like a dead short, so it lets more highs through.
Title: brighten tone as volume pot on guitar reduced?
Post by: RedHouse on June 03, 2004, 10:11:53 PM
The cap by itself can be kinda schplanky sounding as you turn down the ctrl, going from full tone at full vol, to squawky at half vol.

It is a bit better if you add a series resistor with the cap, a value in the neighborhood of half (or a bit less) of the pot's total resistance works very well. Makes it so the tone stays very nearly the same as the knob is turned down.

For a 250k Vol pot use a 130k resistor, for a 500k vol pot use a 250k resistor, start in this ballpark and adjust to your taste, you might be surprised how linear you can make the tone stay with the volume.
Title: brighten tone as volume pot on guitar reduced?
Post by: Paul Marossy on June 04, 2004, 11:00:42 AM
I used a 0.001uF cap on the volume pot of two of my guitars, and I have no problems with it.