Guy from Disclosure breaks down the bass on Mac Miller's 'Blue World', built from a real bass guitar layered with a synth sub to fill the low end without stealing focus from the vocal.
The bass guitar has its low end rolled off entirely, leaving just mid character. Guy adds a simple synth sub underneath, that is tuned across octaves with a plucky envelope. The synth sub supplies the low-end weight the bass guitar can't.
Tape saturation glues the two bass layers together so they interact instead of sitting as separate elements.
Guy runs double sidechaining on the bass: a light overall volume duck, plus a multiband compressor that only pulls down the sub frequencies against the kick and clap. That keeps the sub of the kick and the sub of the bass from clashing and wasting energy in a range you barely perceive anyway.