Watch the Triplet Time online guitar lesson by David Santos from 50 Bass Grooves You MUST Know
This is in 12-8. It is a repeating 8 bar form. The bass line feeling comes from the feeling of a triplet. The major third, fourth, and fifth of each chord scale are employed in creating this feeling. There is a two 7 chord in measure 7 which leads to a five 7 chord which brings us back to the top of the form. There is only one chromatic line in the tune, in bar 8, connecting the one chord to the five chord.