Jacobs was born in Brooklyn, New York. For most of his childhood, he lived in Tampa, Florida, but moved back to New York with his mother in 1975. It was during this stint that he first discovered hip hop music while it was still in its underground developmental stage. He bought himself a set of turntables, and was mentored in the craft by his cousin Rene Negron and their close friend Shah-T of the Queens parody rap group No-Face. Shah-T suggested that Jacobs should use the moniker "Shah-G". Jacobs liked the idea, but mistakenly thought that he had said "Shock G", and began using that name instead. In 1978, after getting into too much trouble in Queens, Jacobs was sent back to Tampa to live with his father.
He dropped out of Chamberlain High School to form the Master Blasters, a mobile deejay crew that featured three DJs and four emcees at its height. The group would perform at parties, and eventually caught the attention of WTMP-FM program director Tony Stone. Stone offered Jacobs, who was sixteen-years-old at the time, a job deejaying on the station, which Jacobs accepted. Under the moniker Gregory Racker, he was the youngest radio personality in central Florida with a regular time slot. After being fired for playing the fifteen-minute-long album version of Funkadelic's "(Not Just) Knee Deep" in a five-minute time slot, and also after tensions with his father escalated, Jacobs found himself backpacking through the United States for a few years, drifting through various jobs and participating in petty criminal adventures. It was during this journey that Jacobs' focus shifted from deejaying to keyboard playing, and effectively taught himself to play the piano by utilising piano practice rooms at music stores and colleges around the country.
Deciding to pursue music seriously, he returned home, obtained a diploma, and began attending Hillsborough Community College in Hillsborough County, where he studied music theory.
Years later, Jacobs decided to settle in the Bay Area, moving to Oakland and working at a local musical equipment store. It was while working here that he formed his group Digital Underground with close friends James "Chopmaster J" Dright and Kenneth "Kenny K" Waters.
- 2004: Fear of a Mixed Planet