Naa, it's the shape, and only the shape.
If you see a jazz bass with any other picksups, you'll still say "a jazz with humbuckers", or whatever.
There's been many variations of placements of the pups over the years too, so cant base it on that.
Base it on the sound? Nope. Any shape can have the sound, but you still wouldnt call it a jazz bass.
The neck? Maybe. If you use a jazz neck you'll say "its a X, with a jazz neck!". So theres half of it I guess.
It all comes back to the shape we all know and love. Same with a precision. Also just the shape.
If you see a jazz bass with any other picksups, you'll still say "a jazz with humbuckers", or whatever.
There's been many variations of placements of the pups over the years too, so cant base it on that.
Base it on the sound? Nope. Any shape can have the sound, but you still wouldnt call it a jazz bass.
The neck? Maybe. If you use a jazz neck you'll say "its a X, with a jazz neck!". So theres half of it I guess.
It all comes back to the shape we all know and love. Same with a precision. Also just the shape.