Apple Approves Audiobus For Streaming Audio Between Apps

Guest post by Eliot Van Buskirk of Evolver.fm.

In the beginning, there were music apps, and it was good.

However, each app existed in its own little silo. If you were an amateur or pro musician with apps for playing instruments, recording, adding effects, writing songs, remixing, or making loops, you had to output the audio all the way to a computer or the cloud, then reimport it into other apps, assuming both of them had the appropriate import/export features — or use an actual, like, wire, and run it from one iOS device to another.

By December 2010, Sonoma Wireworks figured out how to add audio copy/paste to music apps on iOS. The team convinced many other developers to adopt the standard, so even at that early stage, 40 developers supported the audio copy/paste standard. Things were better, but you still couldn’t send audio or audio commands from one app to another in real time.

In September 2011 came Virtual MIDI, which moved things along by letting apps send MIDI commands to each other. However, MIDI is not sound — it’s an ancient data protocol from the early days of digital music production that describes when to play a note, how long to play it for, what note to play, and so on. MIDI is still great, and it’s quite useful on and off iOS to this day, but again, it’s not sound.

Things being the way they are — i.e. constantly evolving — someone then figured out how to take things to the next level: Audiobus, which Apple approved on Thursday morning, as Evolver.fm recently confirmed (updated), though it is not yet in iTunes. Audiobus consists of an app that users install on iOS, as well as an SDK for developers.

“Audiobus is analogous to audio cables,” developer Michael Tyson told Evolver.fm in April when Audiobus was in alpha. “It lets you stream audio between two apps, on the same device… Users will be able to stream the output of audio apps straight into other apps, e.g. live-loopers or DAWs [digital audio workstations], playing along in sync with tracks.”

Basically, one musician on a single iOS device will be able to, say, record a virtual cello played in one app using the multitrack recorder in another, daisychain effects together, and so on.

iOS Musician calls this “the next big thing” in iOS music production. Evolver.fm heartily concurs. If you’d like to be alerted when Audiobus goes live, sign up for the official newsletter or follow us on Twitter.

Update: Tyson tells us that the WiFi feature, which would allow multiple musicians to jam together over WiFi with any Audiobus-compliant app the way they already can with Apple Garageband, might not be part of the Audiobus app, at first anyway:

“We’re not currently set on whether [Wifi is] going to be included in our initial release,” wrote Tyson. “We want to make sure it’s a really solid experience over WiFi, and at present, WiFi is problematic in environments with WiFi interference.”