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previous: scott J, if you are out there. Look at th... -- 11/8/2003 7:00 PM View Thread

Re: What kind of treble bleed mods work best?

11/17/2003 6:23 PM
Bradster
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Re: What kind of treble bleed mods work best?
In my opinion the series resistor and capacitor make the very best sounding treble bleed, I call it a "compensation" circuit rather than a bleed because although it does bleed treble when carefully balanced is actually compensates the tone lost when the vol ctrl is used.  
 
Without the resistor, the beed sounds "quacky" and midrange'ey, I've experimented with treble bleed a lot over the years and this is where I'm at:  
 
Use a resistor of at least half the value (or more) of the pot it is attached to, for instance a 500k volume pot needs a resistor of at least 250K in series with whatever tone cap you choose, a 250K volume pot needs at least a 130k resistor.  
 
Then one chooses the capacitor to satisfy the treble you are trying to bleed in.  
 
My personal best for a 500k Les Paul vol pot has been using a 330k resistor with a .0015uf poly cap in series, and for Strat a 180k/.001uf  
 
Just my opinion, but I feel that guitar volume controls w/o at least some kind of compensation just muddy up the tone too-much when turned down.  
 
Here is how I dial in the right stuff for myself and others, I use a home made "resistor substitution box" which has a 250k and 500k pot and various caps installed on a switches, I temporarily solder the output of the guitars selector switch directly to the output jack, reassemble the guitar, plug it into into the home made sub box and into actual amp that is used.  
 
When you play with your band note the levels on the amp's knowbs, you MUST do this testing at those levels (like stage level+) because your tone changes as your amp's output level is adjusted.  
 
Early on when I first started experimenting with treble-bleed I would do the mod in my shop, then try the guitar at night live with the band, it just didn't sound the same as when done in a reduced environment you have to mod the circuit at the levels you intend to play or a bit louder even so it doesn't get undesirable if you have to turn it up.  
 
Just my opinion,  
-Brad