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Discussion Starter · #1 ·
I took a picture of this at a friends with possibly the idea of implementing it on something I have but I don't remember what its supposed to do and now I'm too afraid to ask him?

Anyone know?



 

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Pic wasn't showing for me...so I hope this helps.

I think that is a treble bleed circuit on the volume pot (i.e., resistor and capacitor in parallel).

Not sure why there is a 470K ohm resistor from the switch to ground.
However, it could be a somewhat typical mod. I'm not familiar with the various Tele circuits. Interesting.

 

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Discussion Starter · #3 ·
Pic wasn't showing for me...so I hope this helps.

I think that is a treble bleed circuit on the volume pot (i.e., resistor and capacitor in parallel).

Not sure why there is a 470K ohm resistor from the switch to ground.
However, it could be a somewhat typical mod. I'm not familiar with the various Tele circuits. Interesting.

weird about the picture not showing but thanks for reposting

I am pretty sure I had the treble bleed conversation before snapping the pic so that makes a bit more sense now. Is the 470 a possible cocked wah mod?
 

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The additional fixed resistor changes the taper of the volume pot. The cap comensates by allowing treble to pass unattenuated as the volume is turned down (no effect of the cap when the volume is up full). Changing the resistance taper of the pot alters how much treble is retained, relative to the rest of the signal, at lower volume settings.
 

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That would have been my guess. However, why the value of 470K ohms?
The additional fixed resistor changes the taper of the volume pot.
@mhammer Are you talking about the 470K resistor that is between the switch and the the ground connection of the volume pot?

The purpose of the resistor is to compensate for a P90 through a 250k volume pot. And the reason for not having a 500K vol pot is to service the single bridge coil.:)
@Swervin55 made this comment. Is this also the purpose of the the same 470K resistor?

Can someone please clarify this for me and comment as to how using the value of 475K was determined.

Thanks
 

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Ignore the added cap fot the moment. The pot divides the voltage from the pickup/s, based on the ratio of the resistance between the wiper and input, and the wiper and ground. The smaller the first resistance is, relative to the second, the less the voltage is divided. The optimal case is when the pot is turned up full, such that the first resistance is zero, and the second is 250k.

Adding the fxed resistor places it in parallel with the "first" resistance. That reduces the combined parallel value of input-to-wiper andadded fixed resistor. If the pot was set to 100k/150k (first/second resistance), the added 470k results in the first resistance actually being 82.4k. So, the added resistor changes the shifting value of the first resistance, and consequently the "taper" of the pot.
 

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When I wired my Tele with a neck Humbucker and 500k pots, I followed a diagram that used a 470k resistor in parallel with the hot bridge lead to the pot, which supposedly made the bridge “see” closer to 250k and thus not be so bright. I’m not sure if it was effective as I found it pretty bright and usually ran it with the tone rolled back to about half. I recently switched to all single coils and 250k pots.

Was I doing it wrong?
 
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