CJK84 said:So why the separate casings?
Is there a single winding?
No, two seperate sets of winding.
It's to cancel the 60 cycle hum that most single coil (jazz) pickups have. By placing them staggered like that, it creates a humcancelling effect (hence the term humbucker). So, you have two components, yes, but one sound, one output; which is why P basses have a single volume pot.