Pots is pots?? (pic)

[Lewguitar]

Wow... just wow.

I bought a guitar a few weeks ago that came with a SD Jazz/Custom 5 combo. Which I wasn't happy with. This was also my first guitar without a tone pot.

Come to find that it has a 500K volume pot. Reading through threads here, learned that a 500K volume pot alone is like a 1M vol + 1M tone.

Today I swapped it with a 250K volume and it has transformed the guitar. It now sounds similar to my other 500+500k guitars.

That's not the way it is.

A 500K volume pot without a tone pot does not result in a 500K volume pot becoming, in effect, a 1 Meg volume pot.

It's still a 500K volume pot with 500K of resistance.

What you experienced is simply that a guitar without a tone pot that is leaking some treble to ground all the time, has MORE TREBLE because MORE TREBLE stays in the signal path instead of leaking to ground through the tone pot.

Even when the tone pot is on "10".

That and the fact (to me!) that the a Custom 5 is too bright.

I'm sure Seymour or whoever created the Duncan Custom tried the Duncan Custom with an A5 magnet and decided against it.

But forum members here experimenting with magnet swaps tried it, liked it, lobbied for it and the next thing you know we had a Duncan Custom 5 as part of the line up.

I hate that pickup with 500K pots. Hurts my ears. Just no fun.

So does a JB with 500K pots.

Seymour uses a JB in his Tele, but with 250K pots.

So what you've discovered is that you ALSO prefer 250K pots when your guitar has extremely bright or sharp sounding pickups.

[Top-L]

That's not the way it is.

A 500K volume pot without a tone pot does not result in a 500K volume pot becoming, in effect, a 1 Meg volume pot.

It's still a 500K volume pot with 500K of resistance.

What you experienced is simply that a guitar without a tone pot that is leaking some treble to ground all the time, has MORE TREBLE because MORE TREBLE stays in the signal path instead of leaking to ground through the tone pot.

Even when the tone pot is on "10".

That and the fact (to me!) that the a Custom 5 is too bright.

I'm sure Seymour or whoever created the Duncan Custom tried the Duncan Custom with an A5 magnet and decided against it.

But forum members here experimenting with magnet swaps tried it, liked it, lobbied for it and the next thing you know we had a Duncan Custom 5 as part of the line up.

I hate that pickup with 500K pots. Hurts my ears. Just no fun.

So does a JB with 500K pots.

Seymour uses a JB in his Tele, but with 250K pots.

So what you've discovered is that you ALSO prefer 250K pots when your guitar has extremely bright or sharp sounding pickups.

I've been reading conflicting advice on that point. Someone said that a 250K volume (without tone) would sound virtually identical to a 500+500.

I also installed an Evolution which I always like with 500+500, but it was too bright in this guitar. And the D-sonic which is not particularly bright, I usually run with 500+500 but it sounded too aggro with a single 500k vol. Now it sounds "normal" with a single 250 volume.

What I learned is that the effect of removing tone control or changing vol pot can be pretty profound. I have a handful of resistors I'd like to test with to try some in between values.

[Lewguitar]

I've been reading conflicting advice on that point. Someone said that a 250K volume (without tone) would sound virtually identical to a 500+500.

I also installed an Evolution which I always like with 500+500, but it was too bright in this guitar. And the D-sonic which is not particularly bright, I usually run with 500+500 but it sounded too aggro with a single 500k vol. Now it sounds "normal" with a single 250 volume.

Good. But the reason your guitar is so bright is because you have no tone control leaking treble to ground.

My PRS guitars have only two pots: a volume and tone control.

I like a lot of transparency and clarity and chime from my neck pickup.

So I modded three of my guitars so only the bridge pickup gets a tone pot.

No tone pot on the neck pickup.

Makes that neck pickup very slightly louder, slightly brighter and slightly clearer.

That's what you're experiencing on BOTH of your pickups because your guitar has no tone pot at all.

[Top-L]

Good. But the reason your guitar is so bright is because you have no tone control leaking treble to ground.

My PRS guitars have only two pots: a volume and tone control.

I like a lot of transparency and clarity and chime from my neck pickup.

So I modded three of my guitars so only the bridge pickup gets a tone pot.

No tone pot on the neck pickup.

Makes that neck pickup very slightly louder, slightly brighter and slightly clearer.

That's what you're experiencing on BOTH of your pickups because your guitar has no tone pot at all.

I'm not disagreeing. What I read in another thread, one of the users (who ran a Spice simulation, which is an EE program), found that the frequency response of a single 250K vol, will be virtaully identical to a 500Kvol +500K tone (both on 10).

So far, I can confirm that the D-sonic with a 250K vol is much closer to 500k+500k than it was with just a 500K vol. I'd like to try some in-between pot values, using a resistor to create 300,350,400, etc. Having precise control of the top end is important to me. When the guitar has too much presence, I have to lower the amp's treble/presence and the sound has less cut. IN that sense, having a warmer guitar allows me to have a more articulate, cutting tone.

[Lewguitar]

I'm not disagreeing. What I read in another thread, one of the users (who ran a Spice simulation, which is an EE program), found that the frequency response of a single 250K vol, will be virtaully identical to a 500Kvol +500K tone (both on 10).

So far, I can confirm that the D-sonic with a 250K vol is much closer to 500k+500k than it was with just a 500K vol.

That may be. I don't know.

You're just talking about the way it sounds now and maybe they do sound similar.

I couldn't get my tone without a tone pot on my bridge pickup.

I like those Eric Clapton "woman tones" from when he played Gibsons, and Eric Johnson violin tones, and that how you get 'em: turn the tone control way down

[Mincer]

I think I am the same way- I couldn't get my tone without a tone control, and I am constantly manipulating it.

[Top-L]

I think I am the same way- I couldn't get my tone without a tone control, and I am constantly manipulating it.

I never use it.

I'm thinking of converting the tone control on some of my guitars to a rotary indent with various resistors to change the value of the volume pot.

According to the Fralin article I linked, it should be possible to use resistor to change the "value" of the vol pot. Still not clear if this will do that same thing as another pot.

[GuitarDoc]

I'm not disagreeing. What I read in another thread, one of the users (who ran a Spice simulation, which is an EE program), found that the frequency response of a single 250K vol, will be virtaully identical to a 500Kvol +500K tone (both on 10).

So far, I can confirm that the D-sonic with a 250K vol is much closer to 500k+500k than it was with just a 500K vol. I'd like to try some in-between pot values, using a resistor to create 300,350,400, etc. Having precise control of the top end is important to me. When the guitar has too much presence, I have to lower the amp's treble/presence and the sound has less cut. IN that sense, having a warmer guitar allows me to have a more articulate, cutting tone.

I'm beginning to think that you do too much reading and not enough playing and listening. Keep in mind that you can find ANYTHING on the internet...someone may even say that the 250k pot is brighter than a 500k pot and even back it up with some data.

You can see that even on this one thread there are conflicting statements about the tone of 500k + 500k vs one 250k.

Just because someone says it, doesn't mean it's true. And it doesn't even really matter...accept what people say as their opinion, then try it out and see if it works for you.

[ArtieToo]

. . . then try it out and see if it works for you.

Yup. Personal experimentation is the holy grail.

[freefrog]

.someone may even say that the 250k pot is brighter than a 500k pot and even back it up with some data.

All is a question of situation...

Take two linear pots, one measuring 250k and the other 500k. Mount them as volume controls.

Full up, obviously, the 500k pot will make the sound brighter.

But once lowered @ 50%, what happens? The linear 250k pot puts 125k only between the pickup(s) and output + 125k between output and ground. The 500k puts twice this resistance on each half of the voltage divider... in such a way that @ 5/10, the linear 250k volume control might/may/could/should make the resonant peak 2dB higher and the tone brighter... at least if other parameters (cable capacitance, input impedance) are typical.

FWIW : hasty sum up of experiments / measurements done here for a long time. :-)

I'm not disagreeing. What I read in another thread, one of the users (who ran a Spice simulation, which is an EE program), found that the frequency response of a single 250K vol, will be virtaully identical to a 500Kvol +500K tone (both on 10).

Yes. No. Almost…I’d venture to say that in fact, physical reality is a bit more complex than this… and might change totally according to the context involved.

If you swap a single 250k volume pot for a 500k volume + a 500k tone then compare the sounds with all these pots @ 10/10, you may/might/ could/ should hear (or not) a subtle difference due to the possible influence of the tone cap on upper harmonics... but the difference should be precisely that: "Subtle". And the core tone / overall brightness should stay similar. Reason: the resonant peak should have exactly the same height in the two cases because this prominent frequency is set by the resistive load paired with the pickup(s). A cap between a tone pot and ground tends to change upper harmonics only from 10/10 to 3.5/10 approximatively (then it shifts down the resonant frequency so drastically that it affects fundamental notes, but that’s another story).
As a side note, I’ll just add that paradoxically, the influence of a tone cap on the sound with a tone pot full up should be more noticeable with a LOW value capacitor (like 0.0022µF = 2.2nF) than with a standard one (like 0.022µF = 22nF)... that’s all the mystery of impedance… But you might also notice no difference at all: again, it depends on the physical & musical situation in its globality.

So, I totally agree with the idea that nothing replaces personal experience with such things – and that my wordy clumsy post was therefore not necessary. LOL! :-)

[Top-L]

All is a question of situation...

Take two linear volume pots, one measuring 250k and the other 500k.

Full up, obviously, the 500k pot will make the sound brighter.

But once lowered @ 50%, what happens? The linear 250k pot puts 125k only between the pickup(s) and output + 125k between output and ground. The 500k puts twice this resistance on each half of the voltage divider... in such a way that @ 5/10, the linear 250k volume control might/may/could/should make the resonant peak 2dB higher and the tone brighter... at least if other parameters (cable capacitance, input impedance) are typical.

FWIW : hasty sum up of experiments / measurements done here for a long time. :-)




Yes. No. Almost…I’d venture to say that in fact, physical reality is a bit more complex than this… and might change totally according to the context involved.

If you swap a single 250k volume pot for a 500k volume + a 500k tone then compare the sounds with all these pots @ 10/10, you may/might/ could/ should hear (or not) a subtle difference due to the possible influence of the tone cap on upper harmonics... but the difference should be precisely that: "Subtle". And the core tone / overall brightness should stay similar. Reason: the resonant peak should have exactly the same height in the two cases because this prominent frequency is set by the resistive load paired with the pickup(s). A cap between a tone pot and ground tends to change upper harmonics only from 10/10 to 3.5/10 approximatively (then it shifts down the resonant frequency so drastically that it affects fundamental notes, but that’s another story).
As a side note, I’ll just add that paradoxically, the influence of a tone cap on the sound with a tone pot full up should be more noticeable with a LOW value capacitor (like 0.0022µF = 2.2nF) than with a standard one (like 0.022µF = 22nF)... that’s all the mystery of impedance… But you might also notice no difference at all: again, it depends on the physical & musical situation in its globality.

So, I totally agree with the idea that nothing replaces personal experience with such things – and that my wordy clumsy post was therefore not necessary. LOL! :-)

The new guitar with a 500K vol (and no tone control) didn't sound "right" with any of the pickups in there. When I replaced the pot with a 250K, everything sounded great and virtually identical to how the pickup sounded in a 500+500 guitar.

So I agree that one needs to test, but if it wasn't for the "theory" pointing me in that direction, I probably never would have tried it. For a couple reasons:

1) Because "everyone knows" that 500K pots are for humbuckers.
2) Because "everyone knows" that the existence of a 500K tone pot on full makes very little difference to the sound.

IME, the lack of a tone pot made a BIG difference on the top end. (Now I'm going to have to check all the tone caps in my guitars to see what values they are.)

If I had listened to the other side of the argument (or conventional wisdom), I may have stayed with the 500K pot and never bonded with the new guitar.

[freefrog]

The new guitar with a 500K vol (and no tone control) didn't sound "right" with any of the pickups in there. When I replaced the pot with a 250K, everything sounded great and virtually identical to how the pickup sounded in a 500+500 guitar.

So I agree that one needs to test, but if it wasn't for the "theory" pointing me in that direction, I probably never would have tried it. For a couple reasons:

1) Because "everyone knows" that 500K pots are for humbuckers.
2) Because "everyone knows" that the existence of a 500K tone pot on full makes very little difference to the sound.

IME, the lack of a tone pot made a BIG difference on the top end. (Now I'm going to have to check all the tone caps in my guitars to see what values they are.)

If I had listened to the other side of the argument (or conventional wisdom), I may have stayed with the 500K pot and never bonded with the new guitar.

For the record, I had to cure a couple of times the problem of a "too bright" sound with tone pots whose connections were erratic... For instance, the mere fact to turn on the tone control would put a pressure on the pot and disable it electrically... resulting in a painfully harsh sound. Conversely, I had once to take care of a guitar with a 500k tone pot whose actual resistance was... 50k. No need to say that it was rather dull sounding. :-)

Conclusion? Yes, the presence of a "proper" resistive load is most often critical, tonally speaking.

Glad to know that you've solved your problem, anyway. Enjoy with your reborn guitar! :-)