The simplest bass line is just playing the root note of each chord - one note per chord, down in the low register. It might sound basic, but this is the base of the stock - everything else builds on top.
What is the root?
The root is the note a chord is named after. C major's root is C. A minor's root is A. The bass player's first job is to anchor each chord by playing its root note in the low register - like a chef starting every dish with the base ingredient.
Root notes for a common progression
C major
Bass plays: C
Am
Bass plays: A
F major
Bass plays: F
G major
Bass plays: G
C (MIDI 36) - a typical bass register root note
Why root-note bass works
Defines the chord
The lowest note tells the ear what chord is playing. Even if the chords above are ambiguous, the bass root grounds everything.
Never clashes
The root is always consonant with its chord. You can't go wrong harmonically.
Leaves space
Simple bass lines give the other instruments room - like a stock that supports every flavour without overpowering any of them. In dense mixes, a simple root bass can sound better than a busy one.
Even roots have rhythm
Playing the root doesn't mean playing one long whole note. How you time the root note changes the feel completely.
Same root, different rhythms
Root bass by genre
Pop / singer-songwriter
Roots on beats 1 and 3, simple and supportive. Stays out of the way of vocals.
EDM / house
Sub bass on the root, often sustained or following the kick pattern. Simple but powerful.
Punk / rock
Roots on eighth notes, matching the power chords. Simple, aggressive, driving.
Hip-hop / trap
808 sub bass on roots, often with pitch slides. Sparse but massive sounding.
Key takeaway
The simplest bass line is just playing chord roots in the low register. It's always harmonically correct, defines the chord for the listener, and leaves space for everything else. The rhythm of the root note matters as much as the note itself - same root, different feel.
Next: octaves and fifths - adding just one or two more notes to create movement.
Generate bass lines instantly
Starts creates bass lines that follow root notes, use octaves and fifths, and lock with drums.