For anyone who may be wondering what it means to play lead bass in a band…it does not mean that there is more than one bass player. The easiest way to explain it is to give an example: Cliff Burton. Burton was known for his lead bass approach, in which the bass played a melodic and soloist role, in addition to holding down the harmonic and rhythmic foundation of the band.
Behold, one of my favorite Metallica songs, Orion. The following is just the bass and drums. There are NO guitars playing.
Still pretty melodic, eh? You can easily tell what song is being played.
Full studio version: