Volume Pot 250K or 500K?

[DaveC]

Re: Volume Pot 250K or 500K?

Resurrecting an old thread. . .

A few months ago I installed a pair of Bill n Becky Lawerence L90s in a semi hollow Ibanez AM 50. I used 500K pots for both volume and tone, and .015 mf caps on both pups.

The guitar was so shrill it hurt my teeth. I had to turn the tone pot down to 1 or 2, and even at that I had to dial down the treble on my amp to keep from getting a pain behind my eye sockets when I played it. I have another guitar with P90s that uses 500K pots and it was nowhere near as strident.

I pulled everything out of the guitar, and replaced the volume pots with 250K. I also replaced the .015mf caps with a .470 mf cap on the bridge and a .220 mf cap on the neck.

It sounds really good now. The tone knob on each pickup has a very useable range. It's a realy pleasure to play and offers a palette of sounds that I like.

However, the guitar is indeed quieter. I can't say for certain whether it is precisely as quiet as the 500K pots turned down to "5," but find myself turning my amps up a bit more than necessary with my other guitars. Fortunately, my amps have enough head room that it isn't an issue.

BTW, I used Bourns "premium" mini pots. It's the second guitar in which I've installed them. Very tight tolerances, very smooth feeling rotation, and very useable tapers. I have no interest in the company -- just want to pass on what I believe is a good find.

 

[papersoul]

Re: Volume Pot 250K or 500K?

I wanted to bump this old thread because Blueman335 and I have been talking about this lately. In all my Gibsons, I use 300K
bridge volume pots. To me, even with a 12-15K pickup, the 300K sounds warmer and more pleasing, but still punchy and tight.
On the flip side of that, many guys would rather run 500K pots and just roll the tone back. Some say this results in a completely
different sound but I doubt any of us could hear the difference. I think both approaches are fine. But, since I usually run my tone at 6 or 7,
it makes sense for me to use a 300K and maybe even a 1 Meg for the neck pickup.

 

[Bludave]

Re: Volume Pot 250K or 500K?

When can/should you use a 500K vs. a 250K volume pot? Like what's the difference on volume?

I kinda get how the tone knob would work on 250K and 500K, like where 250K is better for single coils because the latter would brighten it up wayyy too much, while the 250K holds back a humbucker I guess. Where does the volume control's number come in though in all of this?

Generally speaking you would use 500K with humbuckers & 250K with single coils. This is not necessarily followed by all but the 500K pots tend to create more treble & the humbuckers tend to be a touch muddier so the 500K adds treble and balances out the humbuckers. If you have a guitar that is overly bright you can tame some of this by changing a 500K to 250. There are also cap changes that can help this as well.

 

[Kosh Naranek]

Re: Volume Pot 250K or 500K?

Not that the original poster still needs to know, but there are certain humbuckers that I think were designed with a 250k volume pot in mind.
The Duncan JB sounds thin, jangly and ear piercing when wired to a 500k ohm pot. However, it sounds fat, edgy and has great harmonics when wired to a 250k pot. Keep in mind that the JB was introduced back when some players were first starting to route out the bridge area of their Strats to install a humbucker on a guitar with one factory 250k ohm pot, and I think that is the explanation for why the JB is wound to sound best with a 250k pot.
I also once had a Pearly Gates with Strat spacing in a guitar with a 500k pot and it also sounded thin and brittle. I sold the pickup, not realizing at the time that it is would to sound like a Pearly Gates only when installed in a Strat type guitar with 250k ohm pot.

Other humbuckers are wound with a 500k pot in mind. I had a Screamin Demon in a guitar once, and it always seemed like I couldn't get the harmonics out of it that I wanted. I found out the guitar had a 250k ohm pot wired to the bridge pickup. I replaced it with 500k, and the tone is all there now. It's a mahogany body Les Paul scale guitar so it needed the added harmonics.

I also once made the mistake of thinking that 500k pots were better across the board and put them in a Strat type guitar with three SSL1's. When I compared it with another guitar with single coils, the guitar with the 500k pot sounded brittle and thin.

The value of the pot wired to the pickup affects the circuit's resonant frequency and the Q, or width of its resonant peak. A pickup and a volume pot are a simple LR circuit. If I recall correctly from electronics class, the resistor has an effect on Q, which is how wide and gentle or how steep and sharp the resonant peak is.

Lastly, I have never noticed an appreciable change in volume when switching to a different value of volume pot. Just a significant change in tone.

 

[blueman335]

Re: Volume Pot 250K or 500K?

Too many players automatically that assume one pot value is for all HB's and another for all SC's. This is really simplying things. With string energy producing very different tones in the bridge and neck slots, that should also be a consideration in choosing pot value. Neck slots are warm, middy, and bassy. Bridge slots are bright, sharp, and thin. Guitar manufacturers like to use one value for all the pots they put in a guitar for cost and simplicity reasons: less parts to carry in inventory and no chance of getting the wrong pots used in the assembly process. Somehow this gets construed into having some sort of insightful tonal significance on the manufacturer's part.

I think most payers would agree that neck PU's are plenty warm as it is, and 500K pots are needed for clarity and definition. However, this is not a concern for most bridge PU's, being located in a very bright location to begin with, hence using the tone pot to remove the treble that was allowed to flow thru by using 500K pots. Seems kind of illogical to me, add and remove the same frequencies. My EQ efforts with neck PU's are all in the same direction: to enhance clarity and high-end to avoid a muffled, muddy sound. With bridge PU's they're all in the opposite direction: to add warmth and mids for a fuller, richer sound.

My advice is to use the pot values that you think are needed to get the tones you want, not the tones someone else wants, especially since they're playing different guitars and amps, and often different styles of music. Think for yourself. You may decide on 500K's for all your HB's. That's fine. The point is that it should be your decision, based on your ears. Your guitar, your tones, your music. Woods vary in tonal characteristics. PU's sound very different in a LP vs a Strat. I find it hard to believe that one pot value is best for all HB's in all guitars for all genres of music.

To some people this is hereasy, and they've tried to shout me down over the years.

 

[post toastie]

Re: Volume Pot 250K or 500K?

Too many playersautomatically that assume one pot value is for all HB's and another for all SC's. This is really simplying things. With string energy producing very different tones in the bridge and neck slots, that should also be a consideration in choosing pot value. Neck slots are warm, middy, and bassy. Bridge slots are bright, sharp, and thin. Guitar manufacturers like to use one value for all the pots they put in a guitar for cost and simplicity reasons: less parts to carry in inventory and no chance of getting the wrong pots used in the assembly process. Somehow this gets construed into having some sort of insightful tonal significance on the manufacturer's part.

I think most payers would agree that neck PU's are plenty warm as it is, and 500K pots are needed for clarity and definition. However, this is not a concern for most bridge PU's, being located in a very bright location to begin with, hence using the tone pot to remove the treble that was allowed to flow thru by using 500K pots. Seems kind of illogical to me, add and remove the same frequencies. My EQ efforts with neck PU's are all in the same direction: to enhance clarity and high-end to avoid a muffled, muddy sound. With bridge PU's they're all in the opposite direction: to add warmth and mids for a fuller, richer sound.

My advice is to use the pot values that you think are needed to get the tones you want, not the tones someone else wants, especially since they're playing different guitars and amps, and often different styles of music. Think for yourself. You may decide on 500K's for all your HB's. That's fine. The point is that it should be your decision, based on your ears. Your guitar, your tones, your music. Woods vary in tonal characteristics. PU's sound very different in a LP vs a Strat. I find it hard to believe that one pot value is best for all HB's in all guitars for all genres of music.

To some people this is hereasy, and they've tried to shout me down over the years.

i absolutely agree with you. perfect assessment.

 

[Wyeth]

Re: Volume Pot 250K or 500K?

It's less about tone guys and more about audio taper. For volume controls anyway, you get a smoother audio taper if you match the track resistance of the pot to the impedance of the pickup.

So, generally, 500k with humbuckers, 250k with single coils. If you've got a really hot single coil though, you might want to use a 500k.

Me, I can't really tell the difference with tone controls, and it's not because i'm not sensitive to high frequencies; I can still hear that pitch that only teenagers are supposed to be able to hear, and i'm 53 now.

Mind you, when I was down the hospital last year the nurse told me I had the body of a 25 year old. I told her to shut up or the cops would be digging my garden up...

That is exactly the problem I was faced with, I went with a Seymour Duncan Vintage Hot Stack Plus Strat STK-S7 in the neck and middle position looking to warm up my HSS in the Neck, Middle and Middle/Neck positions. It toned down the quack but I also lost the infamous bell sound and my tone didn't go warm it went brown. I dropped a 500k into the volume pot and I got the tone I was looking for.

 

[Clint 55]

Re: Volume Pot 250K or 500K?

The first time I replaced my 250k volume pot with a 500k I was taken aback at the improvement in sound. I thought something was wrong at first. Then I realized it was the increased clarity allowed by the pot. It was on my strat with antiquities in it. I believe I was on the mustang neck at the time.

 

[rgand]

Re: Volume Pot 250K or 500K?

Years ago, I put humbuckers in my Tele. A Bill Lawrence L500 in the neck and an L250 stacked humbucker in the bridge (look at my avatar photo to see them). For years I used the original 250K pots. One day I changed the vol and tone pots to 500K. I was amazed at the beautiful tones they were capable of. I wished I had done it sooner. If I want them to warm up, I just turn the tone down some. Now I put 500K pots with every humbucker.

 

[GuitarDoc]

Re: Volume Pot 250K or 500K?

Yeah I know, but I am a stickler for precise language.

Well, if that is true, then you need to be precise enough to clarify whether you're talking about the output or the EQ. You are correct if you are referring to the output, but you are wrong if you're talking about the EQ which most people are thinking of when they're talking about tone.

The pot removes treble from the output of the guitar by directing it to ground instead. But by using a pot to reduce treble from the output you are actually increasing the bass and mids of the EQ.

Ex: let's say, for simplicity sake, that you have a pup that has tone of treble=33%, mids 33%, and bass=33% (output and EQ = 100%). Now you cut the treble by 1/2. So your output is now composed of: treble=16%, mids=33%, bass=33%. Treble has been reduced, and total output has also been reduced to 82%. But your EQ always will total 100% so the individual spectral values will now be: treble=20%, mids=40%, bass=40%.

So, relative to EQ, by cutting the treble you have actually increased the mids and bass of the pup.

 

[pawleep]

Re: Volume Pot 250K or 500K?

Resurrecting an old thread. . .

A few months ago I installed a pair of Bill n Becky Lawerence L90s in a semi hollow Ibanez AM 50. I used 500K pots for both volume and tone, and .015 mf caps on both pups.

The guitar was so shrill it hurt my teeth. I had to turn the tone pot down to 1 or 2, and even at that I had to dial down the treble on my amp to keep from getting a pain behind my eye sockets when I played it. I have another guitar with P90s that uses 500K pots and it was nowhere near as strident.

I pulled everything out of the guitar, and replaced the volume pots with 250K. I also replaced the .015mf caps with a .470 mf cap on the bridge and a .220 mf cap on the neck.

It sounds really good now. The tone knob on each pickup has a very useable range. It's a realy pleasure to play and offers a palette of sounds that I like.

However, the guitar is indeed quieter. I can't say for certain whether it is precisely as quiet as the 500K pots turned down to "5," but find myself turning my amps up a bit more than necessary with my other guitars. Fortunately, my amps have enough head room that it isn't an issue.

BTW, I used Bourns "premium" mini pots. It's the second guitar in which I've installed them. Very tight tolerances, very smooth feeling rotation, and very useable tapers. I have no interest in the company -- just want to pass on what I believe is a good find.

Nice info,, thanx..
So i rekon it is ok to use a 2 different value caps for the tones on a strat style guitar? p

 

[esandes]

Re: Volume Pot 250K or 500K?

I always have the tone knobs dimed and I like a bridge HB in strats. So I modded my strat to HSS with a 500k volume for the HB and a 250k volume for the SCs. No tone pots. I am very happy with it. The two knobs are the lower two spots so my pick hand doesn't hit that that old knob next to the old bridge SC.

I can send you the wiring diagram if you're interested. I got the custom pickguard from warmoth.

 

[Mincer]

Re: Volume Pot 250K or 500K?

You can totally use 2 caps if you want to.
Man, I use my tone knobs all the time...although on my Strat the first one is neck & middle and the 2nd one is for the bridge. My 1982 "The Strat' has a master tone, and a strange 2 position switch.

 

[octavedoctor]

Re: Volume Pot 250K or 500K?

I can't say for certain whether it is precisely as quiet as the 500K pots turned down to "5," but find myself turning my amps up a bit more than necessary with my other guitars. Fortunately, my amps have enough head room that it isn't an issue..

There is no reason why it should be quieter. Cap values will always have an effect on tone because even with the pot on maximum value there will always be some level of filtration, and pot values will also affect harmonic content owing to it's effect on the resonant peak of any circuit involving a coil, capacitor and resistor.

Volume controls are wired as potential dividers, which means that when you operate the wiper you are tapping into a voltage gradient at the top level of which is V and at various stages V/x, the value of x depending on whether it is a linear or logarithmic taper to the pot track. So if your pickup has an output of, say, 250mv RMS for a given attack, then it will still be 250mv whether it's got a 250KΩ or 500KΩ or 1MΩ pot attached... What will change is the resonant peak of the circuit and the level at which high frequency components get shunted to earth.

What you may be picking up on is that lower sensitivity that the human brain has to lower and mid range frequencies. If you pull down the top end component of any sound it tends to sound quieter even though the actual intensity of the sound may be the same. In nature, distress calls are generally rich in high frequencies, so they stand out more.

If your guitar's volume is significantly lower though, you may want to check for a dry joint somewhere between the switch and the output jack.

 

[pawleep]

Re: Volume Pot 250K or 500K?

cool thanx
pmpaulmich@gmail.com