Yes, the core of that tone is hands, strings, and pickups. But if you have a bass with old strings, darker sounding pickups, etc, you can kick it into that ballpark with certain preamps. EQ to boost the high mids, and drive to fake the missing harmonic content. The Tech21 stuff is the best I've found for making a dull bass growl.
The new Darkglass Harmonic Booster might be worth a look too. It's a clean preamp from them this time.