I recently put some Fender Custom Shop 60's Jazz Bass Pickups in my late 90's Fender Jazz Bass Deluxe which had Dimarzio Ultra Jazz Pickups. I was hoping for a better tone. The Dimarzio's were too boomy but now the custom shop's are too thin with no bottom end even when boosting the bass. does anyone know if this is because of the preamp or are the 60's thin on the lower end. Anyone have any suggestions for a fix?