1) What does over/underwinding do to the sound/response of a J pickup? 2) What does flat poles vs protruding poles do to the sound/response of the pickup? If I were looking for a bit more punch and low mid out of a J pickup (vs CS 60s), what should I be looking for?
Can't really answer your first two questions, but DiMarzio Model J seems to fit the bill for more punch and low mid response.
All things being equal, overwound typically offers more output and less high end; underwound the opposite This assumes identical pickups (magnets, winding technique, wire gauge & type, etc.) compared to each other. Protruded poles get the magnet closer to the string for a slight volume increase as well as a slightly more robust tone. Agreed about the model J; I've had one in a bass since the early 90's.
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