Ah, what a great question. 😎
So, when I went to learn this kind of stuff, I found that it takes a different mindset and approach to it. The bass isn't going to be the only thing quantized to the track. The drums/percussion and even other bits within the track will be quantized. Essentially, the tracks are divided. (for the techie geeks, engineers and nerds amongst us - I wonder if how we refer to subdivisions of bars in sheet music perfectly correlates to binary, hexidecimal etc? 1-2-4-8-16-32 being the denominator to a note subdivision?).
In your mind, how do you think a digitally expressed music motif would be played? Under the constraints of the technology of the time, I'd think of these;
- Dynamics. They usually stay relatively the same throughout.
- Do they drag, push or play dead on in the pocket? Dead on.
- If you can read music, look at the sheet as if it's a grid divided into 16th notes (32nds if you're playing the likes of Michael Jackson's 'Speed Demon' 🤣). Whilst it's also a great groove exercise, it's also helpful to see where the bass synchronises with the other instruments on the track. If a track is all digitally composed, they will be exactly on. I can't imagine the tolerance (or 'humanising' as Logic Pro would tell you) to be very much, if at all, in terms of 'pocket'.
- On the topic of eliminating 'humanising' in your basslines, I'd recommend some exercises that'll not only help your playing in this realm but they will make your playing so much cleaner in general. If you set your metronome to below 15bpm, leave it running and see if you can hit your notes as accurately as possible to that click. Don't be tempted to embellish or go astray from it. The signs of agitation and frustration are symptomatic of significant improvement. Notice how different your playing is afterwards and be prepared to grin like Cheshire Cat, my low end friend. I call this 'Anti-microflamming'.
- If the bass line goes below a standard low 'E', can your 5 string handle it without going 'floppy'? Your ye olde Casios and Yamaha DX-7s never have/had this issue.
- A bass mute (I know, Motown, right?) is surprisingly helpful. Pop some foam under the strings and right by the bridge for an experiment. Play along with the tracks you so wish to and see if it helps your playing.
I do hope this helps and feel free to ask any questions. If not, my apologies for over indulging here.