Tone Pots - including 'No-Load' pots To go with the tone capacitor, the Tone Pot is the other component of a simple treble-cut tone control.
Lrc potentiometer dating
There's a distinct peak of about +4db even with 250k pots, and that can be increased by use of higher values or a no-load tone pot.
An extreme case is a 1M volume pot and no tone pot, with a rather shrill +13db peak.(As an aside, just a word on these graphs showing peaks etc: They are theoretical values based on a uniform frequency response input.
So they would get modified by the real-world characteristics of a the guitar and pickup.
But they are good for comparing results, ie, although we can’t tell the actual true response of a real pickup from these, a configuration with a higher peak will be likely to have more output at that frequency than one with a lower peak. Carry on....)Moving to the vintage PAF humbucker, all the peaks are at lower frequency, and not as high.
Hence if we want the same sort of peak to perk up the top end response, we need a higher value combination of pots. One might think of a 500k volume and no-load tone for this one, subject to taste of course.
The two 500k’s look pretty good, and it's the same trace as a 250k with no-load pot. In the pursuit of maximum brightness, there are also some adverse factors that should be considered.The larger the tone pot value, the least effect there will be within the upper half of the turn, and the more the main tone-control action will be concentrated down below 5 or less.And for the volume pot, the higher the value, the higher the impedance of the guitar is when it's at mid-volume and the more it is affected by treble loss from the cable. Certainly this works well with 250k and 500k pots, and probably reasonably well with 1M pots (but this needs checking).'No-Load' Pots Fender also names these the 'Delta Tone' system. 'No-load' pots have a break in the conductive track that goes to infinite resistance as you approach maximum.Below that they are almost the same as standard pots of the same value. However, the two I bought from Fender had a more accurate max value around 250k than do many standard pots, which often read a bit low. It works very well particularly with full-sized 24mm pots.But take another look at the graphs and see what they do.Typically, they are adding about 3db of brightness at the high treble peak.