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Discussion Starter #1
I switched the 500K Ohm volume and tone pots to 250K Ohm on the neck pickup of my 335 copy today. I kept the .033 uF cap.

Anyone else done this with humbuckers?

What are your thoughts/conclusions?

I will wait to comment as I don't want to 'contaminate the thread' /'lead the witness(es)' sort of thing.

Thanks for your comments.

Cheers

Dave
 

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I switched the 500K Ohm volume and tone pots to 250K Ohm on the neck pickup of my 335 copy today. I kept the .033 uF cap.

Anyone else done this with humbuckers?

What are your thoughts/conclusions?

I will wait to comment as I don't want to 'contaminate the thread' /'lead the witness(es)' sort of thing.

Thanks for your comments.

Cheers

Dave
A great thread, very curious about the replies!
 

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I've heard that the reason to use 500k pots with humbuckers is to let the 'highs' come through. So I would assume that using 250k pots with humbuckers would produce a darker, more muffled sound. Am I right?
 

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Volume pot value matters most if you tend to leave your volume up full. The moment you turn your volume down a bit, you're loading your pickups down and pot value starts to become moot.

Consider that your volume pot presents two parallel paths to ground from the volume-pot wiper that the next device in line sees. If the pot is up full, one of those paths is the full value of the pot (i.e., 250k or 500k) and the other is whatever the DC resistance of the pickup/s is (somewhere in the neighbourhood of 6-9k). Lets turn down the volume a little. So, now we have, one one side of the wiper, 200k going to ground, and 50k put in series with the pickup/s. We are now pitting roughly 58k against 200k.

From another angle, consider that, when two resistances are placed in parallel, their effective combined resistance is determined primarily by the lower/lesser of the two. So, if the next device in line would "prefer" to receive signals from something with an output impedance of 10k, putting 250k or 500k in parallel with 6k will still get you there (it will be <6k). If we place 200k in parallel with 56k, we end up with around 44k in parallel, which will end up losing us bandwidth. This is why many guitars use a bypass capacitor on the volume pot; so that high frequencies are treated as if NO resistance are added to the load of the pickups from the amp's perspective.
 

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My LP has a Duncan that was wired with a 300K pot along with the mini HB in neck (I think it was original Gibson wiring type). I played on max volume for years, basically just with the Bridge PUP, but the day I started to use the guitar volume and both PUPs, I got it changed to 500K. Total Treble suckage out of the PUPs with 250K. As per @mhammer , I also got the tone POT on the bridge outfitted with a STewMac Treble bleed circuit. Doesn't specifically adhere to your initial question, but it's the best thing I've had done on the LP ever. You can set your tone and turn down the volume without any changes to the sound. I'd think something like that would be sweet on a 335 with HB's as well.

Golden Age Treble Bleed Circuit | stewmac.com

You probably have the components to make one yourself already. Hope this doesn't throw you off your initial query @greco
 

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Discussion Starter #7
Thanks for all of the responses. I was trying to achieve a warmer tone and thought this approach might be an alternate to staying with 500K Ohm pots and going to a .047 uF cap. There is a lot of (mainly subjective) discussion about this on many websites.

It was an itch I just had to scratch...LOL.

The tone now 'appears' to be warmer and possibly somewhat 'thicker'.
However, it might just be me rationalizing that all of the work was worth it.
One of the sales staff at the local music store commented that "Working on a 335 is similar building a model ship in a bottle." ... I like that!

I need to spend some more time turing knobs on both the guitar and the amp.
 

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Not at all!

It is always fun (and educational) for me to read about electronics mods for guitars.
Same. I'm learning something new every day and appreciate when little tidbits roll in that may apply to what's going on with my gear as well. I've pretty much forgotten my Electronics theory and applications, so it's great to take a bit of time now to apply what was learned and forgotten and re learn it in a more meaningful (to me) way.
 

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So if 500k is the norm but using 250k, would that not be like turning your tone knob to 5 on the 500k pots?
 

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You're confusing me here. What is being turned from 500k to 250k, the volume pot? As for what is equivalent to "5 on the 500k pots", that would depend on the taper of the tone pot in question. "5" is the marking on the knob, and may or may not reflect some proportional change in pot resistance, depending on the taper of that pot.
 

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Normally you would have a 500k tone pot on a humbucker. If you put a 250k tone pot, then you are at the equivelent of being at number 5 on the tone pot of the 500k pot, yes? Assuming the taper is the same on both pots for mister nitpicky above me.
 

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or if you like, assuming you have a 500k pot and turn it down to 5, if you read the resistance (at 5) it should be about 250k plus or minus the error, yes? So a 250k wide open tone pot should sound pretty damned close to a 500k pot at number 5. Assuming that both tapers are the same.

Theoretically
 
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or if you like, assuming you have a 500k pot and turn it down to 5, if you read the resistance (at 5) it should be about 250k plus or minus the error, yes? So a 250k wide open tone pot should sound pretty damned close to a 500k pot at number 5. Assuming that both tapers are the same.

Theoretically
From my own experience as explained not very well above....Your i about the right ballpark with that assessment. Maybe not quite as drastic tone wise as 1/2 would suggest, but there is a noticeable difference in my own tone. Treble bleed circuit helped that along after the fact though. Makes the hum/single coil push/pull tone on the bridge nice to use in the Middle toggle position as well.
 
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