Disappointed to report that switching from the original fitted 1966 spec coils that the background hiss is still very noticeable. I’m a confident electrical handling and understanding. My fender precision is silent, as are all my other bass and guitar units, fitted with genuine humbucker units, but this noise prevails on the Jazz Bass. The sound is very comparable so no issues here. The noise aspect is very noticeable when effects are applied eg, chorus when plugged in via the Boss ME 90 B. Not sure what to do now…😳