Does a tone pot actually increase load?

[Antigua]

Does a tone pot actually increase load? The reason I'm confused is because when you turn the tone pot to zero, there's still limited amount of load in the system, unlike a volume control. The pickup is still producing a lot of output at a lower resonant peak despite the pot representing no resistance between the positive and negative sides of the pickup. Is the truth of the matter simply that the tone pot interferes with the efficiency of the pickup, or it's ability to form a strong resonance and thus muffling the high frequencies, but does not literally increase the load?

[Dave H]

The pickup is still producing a lot of output at a lower resonant peak despite the pot representing no resistance between the positive and negative sides of the pickup.

The tone pot is set to no resistance but there is still the impedance of the series capacitor.

Edit:
e.g. If the pickup is 5H and the tone cap is 47n the lower resonant frequency will be 330Hz

[Mike Sulzer]

The tone pot loads the pickup, depending upon where it is set. When set to 0, the pickup is has the tone capacitor in parallel, which drastically lowers the resonant frequency and gives a "bassy" sound. When the tone pot is on 10, it loads the pickup in the region of the resonance, where the pickup impedance is high. At these frequencies, the tone cap has a low impedance, and so the loading effect is very much as if the cap were not in the circuit at all and so just the value of the pot loads the pickup. As the tone pot is turned down, it loads the pickup more, dulling the sounds, and as it is turned further, the effect of the capacitor takes over.

Does a tone pot actually increase load? The reason I'm confused is because when you turn the tone pot to zero, there's still limited amount of load in the system, unlike a volume control. The pickup is still producing a lot of output at a lower resonant peak despite the pot representing no resistance between the positive and negative sides of the pickup. Is the truth of the matter simply that the tone pot interferes with the efficiency of the pickup, or it's ability to form a strong resonance and thus muffling the high frequencies, but does not literally increase the load?

[Antigua]

When the tone pot is on 10, it loads the pickup in the region of the resonance, where the pickup impedance is high. At these frequencies, the tone cap has a low impedance, and so the loading effect is very much as if the cap were not in the circuit at all and so just the value of the pot loads the pickup. As the tone pot is turned down, it loads the pickup more, dulling the sounds, and as it is turned further, the effect of the capacitor takes over.

Thanks, that makes perfect sense.

[bbsailor]

Does a tone pot actually increase load? The reason I'm confused is because when you turn the tone pot to zero, there's still limited amount of load in the system, unlike a volume control. The pickup is still producing a lot of output at a lower resonant peak despite the pot representing no resistance between the positive and negative sides of the pickup. Is the truth of the matter simply that the tone pot interferes with the efficiency of the pickup, or it's ability to form a strong resonance and thus muffling the high frequencies, but does not literally increase the load?

See this link for a technical discussion about how this "no load tone pot" works: GuitarElectronics.com - Guitar Wiring FAQs

Further web searching the term "no load tone pot" also brings up discussions about whether it has any value at all. Let your ears be the final judge.

Joseph J. Rogowski

[Mark Hammer]

As with so many things, the real audible impact will vary with context.

If one is the sort of player that generally leaves the volume pot up full, plays clean, and plays single-coils through relatively short cables (12' or less), you WILL notice an audible difference between having a tone control in place vs disconnecting it in some manner (e.g., via a "no-load" pot).

If you tend to leave your volume pot turned down a bit, or monkey around with it constantly, and play humbuckers, through a 25' cable (or worse, through a pair of them, connected via several true-bypass pedals, with no buffering linking the cables), the chances are pretty good you will not be able to detect any audible difference between having a tone pot turned up to full treble, and NOT having any tone pot.

[Antigua]

There's no question that tone pots make a difference @10 versus fully disconnected. I've installed no loads, and you hear the difference when you hit the 10 mark. The effect will be more or less noticeable depending on the other component values in the circuit, especially more noticeable when the pickup has a higher resonant peak, or a higher Q that stands to drop that much further when load is added.

My question was whether it could be regarded as "added load" since there's a capacitor in series with the pot that never permits the signal to fully ground out, but I accept the explanation that it could be said to "add load" at the higher frequencies, but not the lower ones.