OD Volume pot lower than spec ?

[nkt$275]

As a general rule what effect does using a lower value volume potentiometer have on an overdrive pedal ? I ordered several A500k pots. They range from A440k to A480k. What difference should I hear ? In OD pedals the volume pot is usual the last or near the last component of the circuit.
With electric guitars a higher value lets more high frequencies pass through the circuit. It has to do with the load the value puts on the pickup. Hence Fender 250k vs Gibson 500k.

 

[swyse]

It's going to depend on the circuit and what comes before it, but generally you're creating a high pass filter. If you have a 500k pot and a 100nf capacitor before it, at maximum volume you're going to have a cut off of 3.1hz which will not be audible, and a 440k pot with the same capacitor would be 3.6hz, so not a noticeable difference, The same circuit with the 100nf capacitor and the volume at 10% of the pots value (halfway or a little before halfway depending on the pot with log taper), you have a filter of 31hz at 50k ohms. If you change that 500k pot for a 100k pot your filter range changes from 15.9hz to 159hz at 10% which would be cutting a bit of bass, however you can change the capacitor to compensate.

 

[nkt$275]

Thank You ! Much appreciated. I always over buy potentiometers picking out the closest to the spec value… Trying to control the consistency of the product. It also sets a strong base for modifying the circuit. The sonic output is the sum of the parts. The largest variance seems to be in the potentiometers. I didn’t know if I am being too picky ? ? ?

 

[spi]

I've never bothered to measure a pot I used in a pedal. I don't know if I'm not picky enough, but the way I see it all parts have tolerances and as long as I've got the right nominal value, a bit of variance isn't going to matter. It might accidently improve the circuit.

I have measured pots for guitar, to figure out which to use on the neck versus the bridge.

 

[nkt$275]

Spec on a Humbucking Les Paul is 500k.
Late 1950s Les Pauls usually fall short of that.
I used to go through bags of potentiometers at a local shop looking for 425k. In that circuit it takes off the very high end. For instance if a 1 Meg pot is used… it adds more presence.