princeton bass control question

on my SFPR the bass control only seems useful to about mabe 4, after that there is no increase in bass response, is this normal, or is there something i can do to get more bass from the control, iam changing speakers latter, the amp is a little sharp for my taste, so is there a mod to increase some bass from the control ?

It may have been replaced at some time with a different sweep. There is linear and logarithmic.

Linear changes resistance gradually, logarithmic does so in a similar way to how the human ear hears changing gradients.

My BFPR home-build bass control sounds fine throughout, so I suspect you may want to just replace the pot.

on my SFPR the bass control only seems useful to about mabe 4, after that there is no increase in bass response, is this normal, or is there something i can do to get more bass from the control, iam changing speakers latter, the amp is a little sharp for my taste, so is there a mod to increase some bass from the control ?

I have a non reverb SF Priceton and the tone stack effect is subtle on mine - if you look at the effect of the bass control on the Duncan Tone Stack calculator, the effect of moving it between 4 and 10 is only a few dB at say 82Hz (a low 'E')

http://www.duncanamps.com/tsc/

That translates into a pretty subtle change to the human ear?

I have had several Fender blackface amps, and never had a bass control that did anything past 4 or so. I think that's just the way it is.