[3] Smith began playing bass in 1984 at the age of 14 after he and his high school (Torrey Pines High School, Del Mar, California) friends were looking to form a reggae band, which they named White Lion (seemingly unaware of the heavy metal band of the same name).

This was clear as early as their first record Nà Vuccà Dò Lupù, on which Smith's bass was the only harmony instrument.

In addition to Zach's bass, Pinback songs often include layered instruments, drum machines, and vocals.

Zach Smith also has a solo project called Systems Officer that allows him "to follow through completely his own ideas and concepts" and "to explore the workings of his inner mind and let his ingeniousness flourish".

On May 11, 2004, Zach released a self-titled EP from this project on Ace Fu Records, playing all instruments himself (including drums).

In 2009, Smith released Underslept on the Temporary Residence Limited label, this time collaborating with Pinback and 3 Mile Pilot drummers Chris Prescott and Tom Zinser.