Potentiometer Question?

[Chistopher]

So it's pretty well known that when the volume on a guitar is turned down it reduces the high end. There are many ways to get rid of this, such as treble bleeds and 50s wiring, but I was wondering about simply diminishing without buying caps and/or resistors or messing with the interaction between your knobs.

I heard that pots with more resistance have less of a treble loss affect than ones with lower resistance. So what I was thinking was taking the standard 500k volume and tone from a Lester and replacing it with a 250k volume and a 1 meg tone. Plus you could have a no load pot (without the detent) to have a more subtle treble boost on 10. Is my thinking sound on this? I don't really know too much of the electrical part of this subject.

 

[beaubrummels]

Re: Potentiometer Question?

I would do the 1 meg on the volume and the no load on the tone, or use no loads on both.

 

[Chistopher]

Re: Potentiometer Question?

But a no-load volume results in no output, right? I've heard that somewhere, but I've never tried it to find out if it's true or not.

 

[beaubrummels]

Re: Potentiometer Question?

Could be. I thought I tried one on volume, but now that I think about it, I might have only used it for tone and blend controls.

 

[AlexR]

Re: Potentiometer Question?

With a vol pot when you increase the K rating it will of course make the pickup brighter. But as you turn down the same movement of the pot is reducing more ohms per move. Plus the way that the volume decreases is similar from one rated pot to another. If you swapped out a strat vol pot for a 1M you are not suddenly going to find 3/4 of the turn does nothing then it acts like a 250K pot for the remainder. The voltage divider effect works pretty much the same way regardless.

So without extra components you have a choice - mess with pot interaction or mess with pot/pickup interaction.

 

[Mincer]

Re: Potentiometer Question?

If the problem is that when the volume is turned down, you lose treble, a pot swap can help, but it is a lot more subtle when you add the compression from higher gain, or other signal processing. Active tone controls certainly get rid of this, but I never found it to be a problem. However, pots are cheap, and totally worth experimenting with. If you decide to go down the rabbit hole, report what you find. It is worth it at some point finding the combo of pots that work for you.

 

[Will S-T]

Re: Potentiometer Question?

Stewmac sell the " Jack Pot" a no-load volume pot that takes out all resistance from the
vol and tone pots after the switch. This coupled with a TB mod should solve all your dilemmas.

 

[Jacew]

Re: Potentiometer Question?

There's a caveat that having higher resistance for tone circuit does not contribute the effect higher value volume pot has. I personally prefer 500k volume with low resistance for tone circuit with smaller cap, as it seems smoother.

No-load volume can be very usable and is relatively easy to make from a regular dual-gang pot:



You open the pot and cut the track (grey area in the picture) so ground is lifted when pot is full on.

Another way to lessen the effect of high value pot diminishing high end, is to lower the inline resistance caused by the pot by adding a resistor parallel with volume pot input and output lugs. That does change the taper of the pot as well though.

 

[Clint 55]

Re: Potentiometer Question?

If you have your pot values dialed, don't change them. Pot values affect your tone a lot. 2 500ks are the bread and butter for humbuckers. A 250k volume and 1meg tone will sound worse and work worse. If you want to have the eq be the same all the way through the sweep of your volume pot, use a cap only in the 200pf range across the input and output lugs of the volume pot.

Oh yeah, about your theory. The vol tone system rolls off highs from each pot, not just the tone pot. The volume ruduces highs from resistance which reduces the amplitude of all the highs. The tone reduces highs by using capacitance, which cuts highs above a certain point determined by the cap.

 

[Jacew]

Re: Potentiometer Question?

If you have your pot values dialed, don't change them. Pot values affect your tone a lot. 2 500ks are the bread and butter for humbuckers. A 250k volume and 1meg tone will sound worse and work worse.

It's not necessarily worse. For med/high output singles, 500k may be better or especially neck might end up very muddy sounding. Higher value pots also contribute to the tightness of your tone, but the spiky highs may get problematic, which is why I prefer lower value tone with low value cap. It makes tone to act a bit more like Presence than EQ control.

I haven't tried 1M tone myself, but I'd imagine it to be full on like having no tone circuit at all...

EDIT: Wait, was this about humbuckers...

 

[Clint 55]

Re: Potentiometer Question?

I agree, I like small caps sometimes as well. But 1 meg tones don't taper very well and mismatching pot values colors in a fishy way compared to just standard 2 500ks. Also it won't have the effect that the op was looking for. 50s wiring and treble bleeds are the only way that I'm aware of to have the eq with the volume turned down be close or the same as the volume on full.

 

[Jacew]

Re: Potentiometer Question?

I agree, I like small caps sometimes as well. But 1 meg tones don't taper very well and mismatching pot values colors in a fishy way compared to just standard 2 500ks. Also it won't have the effect that the op was looking for. 50s wiring and treble bleeds are the only way that I'm aware of to have the eq with the volume turned down be close or the same as the volume on full.

Indeed. I've too noticed lower value pots to taper better. That was the main reason I added the resistor between the output and input lugs as I mentioned earlier. It makes regular (Alpha) 500k pot taper even better than standard 250k.

 

[Clint 55]

Re: Potentiometer Question?

That's a good idea. I'm pretty sure all of my guitars with a tone knob match the volume knob in resistance because I think they color better that way. (I used to try always using 250k for tone.) I do the backwards volume pot wiring with input to middle lug and output to left lug which draws out the taper all the way down to 1. I like it that way.