Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: mresistor on July 23, 2021, 08:55:50 am

Title: Fender J Taper Potentiometers
Post by: mresistor on July 23, 2021, 08:55:50 am

I recently noticed that Fender amps used J taper pots for Vol and Tone.  These pots reach 25% at the first half of rotation, then 75% during the last half.  I had always wondered about that on the vintage amps.
My question is "which Fender amplifiers used these J taper pots?"   Has Fender always used them? If not when did they start using them, and did they ever stop using them? 
for example https://www.tubesandmore.com/products/potentiometer-fender-1m-j-taper-solid-shaft-panel-mount

Title: Re: Fender J Taper Potentiometers
Post by: pdf64 on July 23, 2021, 09:25:00 am

I think most Fenders from 63 onwards used vol and treble pots with a taper of about 30%. As did the trem speed, but backwards  :icon_biggrin:
Mid and bass were a 10% taper.
Around the mid 70s, all the pots were moved to the same taper, noted as ‘J’. The ones I’ve checked have been more like 30 than 25%.
The bass control became a hair trigger at about ‘3’.