The first startup sound (or really just a beep letting you know it functioned correctly) was in the Apple 2. A new beep sound was then added to the Mac, the original name that was made for it was let it beep (based off of the Beatles song let it beep). This lead the legal team at Apple to not be happy! The developer at apple then said the famous words in response “So Sue Me.” Then clever old Apple decided to name the sound “Sosumi” SOSUMI.
Let’s teleport to 2016, the Mac Startup Sound that sounds like this is slowly being removed. The amazing sound developer Jim Reekes is long gone, and the Sosumi sound is renamed to sonumi. With this they have ended a tradition of start-up sounds, and how we brought them back
I decided to let you just know in a short term, the reason they brought it back, was backlash. Sonumi was not changed though.