Born on September 29, 1963, in Richmond, California, Les Claypool would grow up to become one of rock's most inventive and eccentric bassists, best known as the founder, singer, and primary songwriter of Primus. With drummer Tim Alexander and guitarist Larry LaLonde, Claypool built a sound around slap bass, absurdist storytelling, and time signatures that seemed to defy the genre entirely, turning tracks like "Jerry Was a Race Car Driver" and "My Name Is Mud" into alt rock radio staples despite sounding like nothing else on the dial. Before Primus took off, Claypool actually auditioned for Metallica after the death of Cliff Burton, though the gig went to Jason Newsted instead. He's since kept busy fronting side projects like Colonel Claypool's Bucket of Bernie Brains and playing bass in the supergroup Oysterhead alongside Trey Anastasio and Stewart Copeland.

On September 29, 1986, Iron Maiden released Somewhere in Time, a bold left turn that brought synthesizers and guitar synths into the band's sound for the first time, layered beneath Steve Harris's galloping basslines and Bruce Dickinson's soaring vocals. The album leaned into a science fiction and cyberpunk aesthetic, partly inspired by the film Blade Runner, and produced staples like "Wasted Years" and "Heaven Can Wait," both mainstays of the band's live sets ever since. Derek Riggs' cover art placed mascot Eddie in a neon lit dystopian cityscape, packed with hidden references to the band's back catalog for fans to spot. Despite some early skepticism from purists over the synthesized tones, Somewhere in Time reached the top ten in multiple countries and is now regarded as one of Maiden's most ambitious records. Produced by Martin Birch.

On September 29, 1997, The Rolling Stones released Bridges to Babylon, an album that found Mick Jagger and Keith Richards experimenting with modern production well into their fourth decade as a band. Alongside longtime collaborator Don Was, the group brought in hip hop and electronic producers like the Dust Brothers and Danny Saber to inject loops and samples into their blues rooted rock sound, on tracks like "Anybody Seen My Baby?" and "Saint of Me." The album's title referenced the ancient Ishtar Gate of Babylon, tying into a massive supporting tour that became one of the highest grossing of the decade. Reviews were mixed on the experimentation at the time, but the record showed a band still willing to push its sound forward rather than coast on nostalgia. Produced by Don Was and the Glimmer Twins, with Rob Fraboni, Danny Saber, and Pierre de Beauport.