On this episode, we’re turning our attention toward the lower end of the musical spectrum: the bass lines that give songs their movement, their personality, and sometimes their most memorable hooks. The bass is often described as the link between rhythm and melody. It locks in with the drums, but it can also wander, answer the vocal, or carry a tune almost by itself. In several of today’s selections, you can identify the song from the bass line before anything else has even entered.