Gentlemen,
Just to make sure, I just checked my 1983 Fullerton '62 Jazz Bass Re-Issue, and for the life of me I can't find a suck knob. True, it was worked on by Jaco's luthier, brass nut, Ken Smith bridge, EMG's (still have the originals and considering putting them back in), so maybe he removed it. Anyway, no suck knob on my Jazz bass, and it has tons of piano-like tone and a rock solid, straight neck.
For those who haven't had the privilege of playing a properly setup Fender product, the right one is truly a joy to play, and creates many of the tones we all know and love. It's just that their typical electronics do not contain a suck knob. No room for it in the control cavity.
Regards,
Tom