Watch the Simmerin' online guitar lesson by Andrew Ford from Focus On: Reggae Bass
Some of these ska bass players had roots in jazz so that becomes evident when you look at bass lines like this one. The chords are changing every 2 beats so there is not a lot of time to outline the harmony, you basically have a foundation note then a transition note to the next chord. In bar 1 we start on the root Bb, go to the third D, then go to F, which is the b7 of our new chord but feels also like it is finishing our triad by functioning as 5. The last note of this bar goes back down to Bb, the minor 3rd. Bar 2 starts on the minor 3rd, goes down to the root C, then over the F chord on beat 3 we have A, the major 3rd, and F, the root. In bar 3 we begin with the root, Bb, again to the major 3rd, D, this time up to the root on beat 3, G, and again back down to Bb, the minor 3rd. Bar 4 starts with the root, C, to the minor 3rd, Eb, whole step to F, the root, and lastly A, the major 3rd. The next 4 bars starts with a 1-5 interval, high Bb, down to F, next we have D which is the 5 of our new chord, and down to Bb, the minor 3rd, no root here. Bar 6 starts with the root, C, down to minor 7, Bb, half step down to our major 3rd, A, and then our root, F. We start bar 7 again with our root, Bb, walking up in a scalar fashion to the 2, C, and to the major 3, D which is also the 5 of our new chord G minor, and on the 4th beat down to the root, G. In bar 8 we have the 1, C up to the minor 3rd, a smooth connection to F, the root and down to the major 3rd, A. Bar 9 has a couple common intervals, 1-3 on the Bb chord, and 1 down to the 5 on the G minor. We repeat our pattern from bar 8 in bar 10. Bar 11 has a 1-5 then 5-1 pattern over Bb and G minor. In bar 12 we start on the root C, then walk down to the b7, Bb, skip way up to the root F of our next chord then way down to the major 3rd, A. Our last 4 bars of this section start with a repeat of bar 9 in bar 13. Bar 14 again walks from the root down to the b7 but then continues walking down to the major 3rd, A, and up to the 5, C. Bar 15 has a 1-5 then 5-minor 3rd pattern over the Bb to G minor, and our last bar of this section has a 5-1 then over the F chord a root down to a chromatic note Eb that transitions to our new bridge section.
The 1st chord here is D minor, we play it for 2 bars so we have a little more time to develop a motif and use different notes. We start on the root in bar 17, D, and walk up the minor triad, to F, then A the 5, then back down to the lower A on the E string. We continue in bar 18 over the same chord playing the root again, D, to the 5, A, down to F, the minor 3rd, completing the triad, and lastly back to the root, D. In bar 19 we change to C minor and start with another triad pattern, C to Eb to G and ending on the octave, C, our next bar we continue our phrase by walking up further to high Eb, the minor 3rd, down to G, the 5, down again to Eb, minor third, and end on the root, C. In bar 21 we repeat the D minor chord but this time break up the walking pattern with some 8th note rhythms. We start with the root, D, then two 8th notes on the 5, A, then another A on beat 3 before ending that bar with the minor 3rd, F, this is a 2 bar phrase so we continue with the octave D, down to the minor 3rd, F, a couple 8th notes again on beat 3, A and F, the 5 and minor 3rd, then end on D, the root. In bar 23 we return to the C minor but for only 1 bar, in this bar we start with a 1-5 motif, then down to the minor 3rd, completing the triad, then back up to the 5, G. In our last bar in this section which is a 5 chord, F that sets up our Bb chord in bar 25 we have an F, the root, walking down to Eb, which is the b7 creating a dominant chord sound, then continue walking in a scalar fashion down to D, the 6, and to C, the 5 which smoothly transitions to our Bb coming up next.
This last 8 bars in our ABA form goes back to the 1-6-2-5 chord progression. Bar 25 has a familiar 1-5, then 5 to minor 3rd pattern. Bar 26 repeats bar 8, root up to minor 3rd, and root down to minor 3rd. Bar 27 repeats bar 9. Bar 28 has a 1-5 over the C minor chord, C to G, then root F down to major 3rd over the F chord again. In bar 29 we have a 1-5 over the Bb, then 5 down to the minor 3rd over the G minor chord. Bar 30 starts on the minor 3rd, Eb, walks down to the root, C, continues walking down to the major 3rd, A of our new chord F, then finally to the root, F. We close out the phrase with our Bb root going down to low F, our 5, up to our new root, G, to the minor 3rd, Bb, lastly a melodic walk from the 5, G of our new chord C minor, down to the minor 3rd, Eb, skipping down to the major third, A on beat 3, and ending on the 5, C of our F chord.