It's quite woody and hollow sounding...Pick and flats, of course.
Sounds more like a Burns Bass, Jazz Bass type to my ears (or sim, Hagstom etc). A Bass with more than one pick up.
Like 'chris_b' said, Dave Richmond, or even Russ Stableford had similar sounds.
From a Chatgpt search:
"Sven Wunder himself plays bass—specifically, the double bass—on his albums (including Eastern Flowers, Wabi Sabi, Natura Morta, and Late Again). He’s a trained jazz double-bassist who began playing at a young age, a fact he's mentioned in interviews and profiles open.spotify.com+15psychedelicbabymag.com+15steppinintotomorrow.com+15.
Credits for Natura Morta list "electric bass" among the instruments used, which, given his involvement as the arranger, composer, producer, and multi-instrumentalist, points to him handling the bass parts .
So on any Sven Wunder album, the bass lines—double or electric—are performed by Sven Wunder himself."
"I couldn’t find any reliable information detailing the brand or model of Sven Wunder’s electric bass guitar. Most available sources—including recording credits for Natura Morta—simply list “electric bass” without specifying manufacturer or model prestomusic.com+8svenwunder.bandcamp.com+8banbantonton.com+8.
Given his background as a trained jazz double-bassist, it’s likely that electric bass serves more as a functional studio instrument for him rather than a signature piece of gear. He frequently records with vintage and analogue equipment, but no interviews or gear rundowns specify the brand of his bass guitar prestomusic.com.
If you're trying to match his tone, you might focus more on his production/mixing approach—vintage analogue gear, tape recording, and a jazz-influenced playing style—rather than the exact bass model.
Would you like help identifying gear similar in tone, or tracking down studio session credits where he might be more specific?"