Behind the music the story of Marimba, the iPhone text toneIn a fascinating post from Kelly Jacklin, the long time Apple software engineer details how he helped create the default text alert sound on the iPhone -- now known as the "Tri-tone" alert.

The history of the the pleasant chime we've all come to know and love stretches all the way back to 1998, nearly 10 years before the iPhone ever hit store shelves.

Back in 1998, Jeff Robbin, Bill Kincaid and Dave Heller began working on an MP3 player for the Mac called SoundJam MP. If the name sounds vaguely familiar, it's because Apple famously acquired SoundJam MP in 2000 and quickly repurposed it into the first version of iTunes.

But in 1999, before an Apple acquisition was on the horizon, Jeff Robbin asked Jacklin if he could come up with a sound to alert a user when a CD burning session was complete. Being a hobbyist musician, Jacklin was up to the task, and he got to work experimenting with various sounds.

I was looking for something "simple" that would grab the user's attention. I thought a simple sequence of notes, played with a clean-sounding instrument, would cut through the clutter of noise in a home or office. So I had two tasks: pick an instrument, and pick a sequence of notes. Simple, right? Yeah, says you; everyone's an armchair musician...

I was really into the sound of marimbas and kalimbas at the time, so I thought I'd try both of those. I also went through bank (after bank) of sounds built into the SW1000XG, auditioning instrument sounds, and found three other instrument sounds that I liked: a harp, a koto (Japanese zither), and a pizzicato string sound (that's the sound a violinist makes when plucking the string, rather than bowing it).

Jacklin recalls that he wanted a simple sound, which meant that many of the sounds he experimented with were just three of four notes long. For all you music buffs out there, Jacklin also mentions that he wanted the sound to have a happy vibe, so he particularly experimented with "notes from the major scale, focusing on I, III, IV, V, and VIII" octaves.

If you'd like the full nitty-gritty as to how Jacklin came up with a plethora of note permutations to choose from, the full article is a must read. But suffice it to say, Jacklin ultimately settled upon a winner, a sound file he called 158-marimba.aiff.

As initially intended, the sound did indeed become the default sound when a disc burning session in Soundjam MP concluded. When Apple transformed Soundjam MP into iTunes, the sound remained part of the app.

Jumping ahead a few years to the iPhone's release in 2007, Jacklin was pleasantly surprised when he discovered that the sound he created many years earlier continued to live on, this time in the form of the default text alert.

So imagine my surprise when the iPhone ships, and the default text message tone is... "158-marimba", now going by the clever (and not actually accurate, from a music theory perspective) name "Tri-Tone". Time goes by, and this sound becomes iconic, showing up in TV shows and movies, and becoming international short-hand for "you have a text message"... Wow! Who'd have thought?

Indeed, I myself have noticed, while watching TV with friends, that when the "Tri-tone" sound happens to be played in a scene, a number of people reach for their pockets to see if they have a message.

Again, Jacklin's full write-up is worth checking out. As an added and extremely interesting bonus, Jacklin's post includes an audio file comprised of sounds he experimented with that didn't quite make the cut.

[Ed. note: It has come to our attention that blockquotes are not working on the mobile version of the site ( and may distort this story, particularly for those reading on the iPad via the Facebook app. We are working on a fix and apologize for the inconvenience.]

This article was originally published on Tuaw.