Warning: overly poetic, non-technical adjectives ahead. I've got a '78 P Bass with nice, clean, mid-heavy stock PU's. My plan is to pull them out, maybe send them off for a rewind, and keep them for future contemplation. In the meantime, I'd like to try something else that will drop in easily and keep their spot warm. Maybe it's just 41 years of accumulated existence, or an inherent characteristic of late-70's vintage PU's, but a little more grunt in the low-mid's would be nice without scooping any of the mid's. I love mid's, but instead of the clean-ish cut these put out, something with more "burp" would be ideal. Yep...burp is how I describe it...beefier, burpy mid's. I can get there a little with rolling off some of the bottom and top ends, but I'm having a hard time retaining enough low end to stay heavy. EDIT: I’ve since learned “burp” is often associated with Jazz basses. I didn’t say full-on “growl” because I think Duff McKagan/GK, but my terminology may not be helpful, so to supplement my clip in post #6, here’s another on from Buddy Walkin...I’m really diggin’ his tone: Nickel rounds get me in the vicinity, especially Rotosound nickels as I think Buddy is using in the clip (without the silks), but a certain thickness is lacking that I suspect isn't an amp/string/fingers issue. Nickels have a spongy, springy feel to them that encourage my fingers to squeeze the notes a little more, and this seems to help get me in the right direction of what I want to hear. I suspect time and diminished output could be the culprit, but suggestions aside from different PU's are welcome.