Cornell Dupree Tele Wiring

[RedPillBlues]

@RedPillBlues have you considered using a push-pull tone pot instead of the toggle switch? That’s how mine is wired. (I don’t have a wiring diagram.)

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Beautiful guitar! Are you using a 3 way switch? Is the push pull giving you the ability to use all three pickups at once?

 

[RedPillBlues]

Thinking about it, the best thing to do would be to use the 500k pots and then add a 500k resistor to the neck and bridge circuit as per the diagram below.

This is very interesting because it puts the 500k pot and 500k resistor in parallel. When you have two resistors in parallel, they become a voltage divided, if the two resistors are the same, the voltage halves. What this means in this circuit is that the single coil pickup will see the 500k pot as a 250k pot and the Humbucker will see it as a 500k pot.

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Doing a little more digging this evening and found this on the Seymour Duncan forum. Copy and pasted below. Some people were complaining about the effect of parallel resistor on the pot tapers. This gentleman was not.

“Re: Remind me again... how do I turn a 500K pot into 250K with resistors?

I have done this quite often. I used a 510k resistor in between lug 1 & 3 of a 500k volume pot. There are no issues with taper.

The problem is the output resistance is not the same as using a 250k, so you lose more high frequencies due to cable capacitance. If using an actual 250k pot, the treble loss would only be half as much.

If you want to make the 500k pot sound more like a 250k, then you need to use 510k resistor in parallel (between lugs 1 & 3), and also use a "treble bleed" capacitor + series resistor combination between input and output of the volume control. My treble bleed is a small 0.00022uF (220pF) capacitor in series with a 150k resistor. I use a low capacitance 10' cable as well. With a 20' cable you should probably use a 0.00033uF (330pF) value capacitor instead.”

Would that treble bleed add any value in your experience?

Closest value I can source for the parallel resistor without painful shipping costs is 470k in either carbon comp or metal film. Close enough?

Also was reading that a Kinman treble bleed maybe a better compromise vs standard one?

 

[black_doug]

Beautiful guitar! Are you using a 3 way switch? Is the push pull giving you the ability to use all three pickups at once?

It’s a 5 way switch. The middle pickup is a humbucker that is coil-splitting in positions 2 & 4, like a Stratocaster.

The tone pot up puts the neck pickup on in position 1 & 3 so I can have bridge + neck in position 1.

Position 3 is the humbucker, (or humbucker + neck if the tone pot is up.)
Position 5 is the neck.

 

[pipthepilot]

I have done this quite often. I used a 510k resistor in between lug 1 & 3 of a 500k volume pot. There are no issues with taper.

The problem is the output resistance is not the same as using a 250k, so you lose more high frequencies due to cable capacitance. If using an actual 250k pot, the treble loss would only be half as much.

If you want to make the 500k pot sound more like a 250k, then you need to use 510k resistor in parallel (between lugs 1 & 3), and also use a "treble bleed" capacitor + series resistor combination between input and output of the volume control. My treble bleed is a small 0.00022uF (220pF) capacitor in series with a 150k resistor. I use a low capacitance 10' cable as well. With a 20' cable you should probably use a 0.00033uF (330pF) value capacitor instead.”

Its like I said before just experiment and find out what you like the most.

Would that treble bleed add any value in your experience?

When it comes to something like adding a treble bleed circuit, it should be thought of a solution to a problem and not just something you add by default. Treble bleed circuits depend on how you use the volume control. If you keep the volume knob at full all the time, there's no point adding a treble bleed circuit. If you gig (or fortunate enough to be able to play your valve amp loud enough at home to get it to fully breakup) you can uses the volume control to push the amp in and out of breakup, rolling off a little bit of volume to get a clean tone and rolling it to full for distortion, you may notice you loose the highs and your clean tone sounds muddy. This is where adding a treble bleed circuit is going to make a huge improvement for you.

Closest value I can source for the parallel resistor without painful shipping costs is 470k in either carbon comp or metal film. Close enough?

Resistor values are something else not to get too hung up on, always use what you have, if it sounds good Happy Days . If not, try a different value.

I don't buy into the whole "Guitar Mojo" thing like what type of cap is better or what type of resistors is going to give you the best tone. Pre CBS Fender guitars are considered some of the best but the truth is Leo used what he had and what was cheapest. Some Pre CBS guitars sound sublime and others ordinary. The reason? Cheap pot and cap values vary significantly and sometime you you get a perfect combination but that perfect combination will never be at exactly 250k pots and 0.047uF capacitance. There are so many great sounding pre CBS teles that have been found to have pots with over 270k, to the point where specialist suppliers will now sell you 270k pots (at a premium) of course. My rambling point being, try what you have to hand even if the value doesn't exactly match the circuit design, you may find a perfect combination that creates a killer tone and starts the next big "mojo" fad

 

[RedPillBlues]

Its like I said before just experiment and find out what you like the most.


When it comes to something like adding a treble bleed circuit, it should be thought of a solution to a problem and not just something you add by default. Treble bleed circuits depend on how you use the volume control. If you keep the volume knob at full all the time, there's no point adding a treble bleed circuit. If you gig (or fortunate enough to be able to play your valve amp loud enough at home to get it to fully breakup) you can uses the volume control to push the amp in and out of breakup, rolling off a little bit of volume to get a clean tone and rolling it to full for distortion, you may notice you loose the highs and your clean tone sounds muddy. This is where adding a treble bleed circuit is going to make a huge improvement for you.

Resistor values are something else not to get too hung up on, always use what you have, if it sounds good Happy Days . If not, try a different value.

I don't buy into the whole "Guitar Mojo" thing like what type of cap is better or what type of resistors is going to give you the best tone. Pre CBS Fender guitars are considered some of the best but the truth is Leo used what he had and what was cheapest. Some Pre CBS guitars sound sublime and others ordinary. The reason? Cheap pot and cap values vary significantly and sometime you you get a perfect combination but that perfect combination will never be at exactly 250k pots and 0.047uF capacitance. There are so many great sounding pre CBS teles that have been found to have pots with over 270k, to the point where specialist suppliers will now sell you 270k pots (at a premium) of course. My rambling point being, try what you have to hand even if the value doesn't exactly match the circuit design, you may find a perfect combination that creates a killer tone and starts the next big "mojo" fad

Sweet! Is it just a matter of soldering the cap legs to left tab and wiper of the volume pot in this diagram? I plug straight in to my tuner and then straight to the amp. Use volume and tone a fair amount.

 

[pipthepilot]

Is it just a matter of soldering the cap legs to left tab and wiper of the volume pot in this diagram?

Yes, thats correct