Mark King's tone during Children Say on the Live At Wembley DVD/video was my standard for a long time. Over the years I've discovered it was from combination of the Jaydee bass, heavily pushed, mic'ed, 10" cones and DI feed into FOH. Not exactly something I could achieve in my home studio without disturbing the neighbours.
Jimmy Johnson's solo'd graphite neck Alembic with Lee Ritenour is particularly nice, too.
More than four strings...John Patitucci in the early days on his Smith was lovely. Ironically, Nathan East's Yamaha BBNEII has never impressed me on his recordings but I've played them in shops many times and loved what I heard.
My Spector NS5CR takes the cake for tone so far though. Lovely, warm, growly sounds...I've yet to play it live but am pretty confident that it would sound amazing. My recent Status purchase has impressed me also - a surprisingly versatile instrument capable of some convincing p-bass tones as well as the classic Status snarl. While the Spector has more growl, the Status is probably a more suitable work horse.