Windows startup sounds have been ubiquitous fixtures for PC users for over 20 years. Less known are the musical minds that composed these sound snippets—and they are some famous ones at that. Let’s have a look at the notable stories behind several Windows startup themes.

Windows 95 / Brian Eno: In 1994, Microsoft needed something less obnoxious than the much-maligned Windows 3.1 TA-DA! for introducing its new operating system. The company approached legendary ambient artist and rock producer Brian Eno (U2, Talking Heads, Coldplay) to compose the start-up ditty for Windows 95. Eno obliged the job despite his stated preference for using Macintosh computers. “I’ve never used a PC in my life; I don’t like them,” Eno said in an interview with John Lloyd and Sean Lock on the BBC’s ‘The Museum of Curiosity’ in 2009.

Eno was handed a long list of Microsoft-like adjectives for basing the composition—words like “inspiring, universal, optimistic, futuristic”—and it was to be no longer than four seconds. From Eno’s own account, he likened the task to “making a tiny little jewel” and that it helped him break out of the artistic rut he was in at the time. Later that year, his collaboration with Luciano Pavarotti, “Miss Sarajevo,” charted in the UK Top 10.

Windows Vista / Robert Fripp: I find it ironic that Microsoft tapped virtuoso guitarist Robert Fripp to compose a four-second startup theme. Fripp’s band, King Crimson, was famous for penning 20-minute progressive rock epics in the late-‘60s and ‘70s. The Vista startup sound, as well as 45 other sounds coded into the operating system, were taken from recording session Fripp conducted at the company’s Redmond headquarters. It featured the guitarist tracking a soundscape of ambient loops and volume swells on his Les Paul. He was joined by TV and film music composer Tucker Martine and Microsoft engineer and musician Steve Ball who also contributed sounds and editing.

The final production has a deliberate “Win-dows Vis-ta” rhythmic progression, with four chords representing the four squares and colors in the Windows logo. Apparently, Microsoft thought it fit “Win-dows Sev-en” as well—the company reused the Fripp startup for its next operating system.

Other startup sound notables: Microsoft staffer Ken Kato composed the Windows 98 theme. He went on to work with 343 Industries studio that enlisted Massive Attack’s Neil Davidge for the awesome Halo 4 soundtrack.

The Windows XP chime came about from a collaborative effort between composer Bill Brown and Emmy-award winning sound designer Tom Ozanich, whose credits include American Sniper and Kill Bill.

In my opinion, the best Windows startup sound of the bunch is Windows NT with its alien mothership vibe. Its unnamed composer remains a mystery.