Bass lines are probably the most neglected aspect of jazz piano. Many players simply become "good enough" at playing bass lines to "get by" and focus on their right hands; they play where they consider the "action" to be.
This is a shame, because there's a lot to be explored in the piano's lower register.
Why don't you devote the next month to playing bass lines? After all, you've got nothing to lose and everything to gain.
Here's what you do:
Pick a tune and
1. Play just the chord roots
2. Play a 2-beat feel (in half notes)
3. Add 8th-note passing and neighbor tones to your 2-beat feel
4. Play a walking bass line
5. If appropriate to the tune, try out various Latin bass lines, such as Bossa Nova, Samba, and Calypso
6. Figure out a bass line to play over a Smooth Jazz/Funk drum groove
Do this enough, and your left hand will never be the same!
Have fun 🙂
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