i would like a bass that sounds like the bass on funky nassau, something like that.. old gritty funk bass!
you cannot find a bass that sounds like a particular recording. you just can't. no bass will sound like "funky nassau" bass. there are way too many factors that affect the low frequencies (i.e. electric bass guitar) when they are mated to magnetic tape... the actual bass guitar itself, the amplifier, microphones used, the mixing board, effects, playing technique, etc...
i can recommend some great equipment that will get you in the that ballpark...
a vintage fender bass. precision or jazz. this is what almost everyone was using bass-wise in the 60s/70s. the new fender guitars aren't made as well. but they will work too for the most part.
a vintage tube bass amplifier. IMHO, this is more important tone-wise than the actual bass guitar. a 70s ampeg svt pushing a matching 8-10 cab is the best choice. but, that is expensive. and SUPER LOUD. other options include: vintage ampeg "flip-top" amplifier. acoustic 360 or 370. (acoustic is the brand name. and the shit is actually solid state. but awesome nonetheless.)
ok, realistically, you probably can't afford all that. hell, i can't either. get a cheap bass that can at least stay in tune and a cheap amplifier that works, and decide for yourself if you really want to play in that ballpark down the road
