I have a borrowed bass right now (1880s German, swell back, viol shape). It's set up purely for jazz (spiros, low action, no bevel on the fingerboard) it came fitted with both a shadow and a realist pickup. The shadow is really harsh and clacky ( the reason I stopped using my own shadow pickup), the copperhead has loads of warm bass but is very light on high frequencies.
I took it out for a gig and tho the copperhead sounded lovely it had no projection. Ended up using my usual realist sound clamp .. still much darker than my own bass, but ok.
So it's a very warm sounding bass.... but are copperhead pickups usually so bassy?
I wondered if the idea is to use both pickups ( shadow and realist) through a mixer. Is that "a thing"? I'm sure plenty of people use just a copperhead tho.