Migration Guide

AudioKit 5.4 to 5.5

Some taps were changed to use async/await which bumped the minimum requirement operating system.

AudioKit 5.3 to 5.4

The interface to AppleSampler was update to be more safe.

AudioKit 5.2 to 5.3

AudioKit 5.3 is a Swift-only package, so it should be usable on iPad's Swift Playgrounds app. To allow for this, AudioKitEX has been moved to its own package, so you will likely have to update your package dependencies to also include AudioKitEX.

AudioKit 5.1 to 5.2

This version update involves separating AudioKit into separate Sub-AudioKits which are included as separate Swift Packages. This way, developers do not have to compile code that their apps don't require. Most users will probably have to include the SoundpipeAudioKit package since that is the one that contained many of the oscillators, effects, and filters. In addition to including the packages, developers may also have to update their files to import the correct frameworks.

Also, please note that some types that did not move into a new package still moved into a new module. For example, Sequencer lives in the base AudioKit package, but code that references it will need to import the AudioKitEX module that is included in that package.

Here is a list of types that moved into a new package, and where they live now.

AudioKit 5.0 to 5.1

The major change in AudioKit 5.1 is that the Node class was changed to be a Node protocol. The parameters and parameter definition system was cleaned up as well. While these are big changes that warrant the version change, they shouldn't affect most users.

AudioKit 4.x to 5.0

In order to ensure high quality for AudioKit 5, some parts of AudioKit 4 have been removed, so the first step in migrating to AudioKit 5 is to determine whether what you used in AudioKit 4 is still available.

Removed from v5

So, first we'll start out with a list of things that are just not in AudioKit 5 in any form:

1. AudioKit 5 has an AudioPlayer but doesn't include the AudioKit's 4's other players AKDiskStreamer , AKWaveTable, or AKClipPlayer. Some of these classes had utility and could/should be brought back to AudioKit 5.

2. The oscillator banks such as AKOscillatorBank have all been removed. They were coded in a way that we have since outgrown. The only polyphonic node left is Synth but we intend on bringing back polyphonic instruments in a well-coded way as soon as possible.

3. Inter-App Audio support has been removed. Apple has deprecated it and Audiobus now supports Apple's AUv3 format, which should work even better than Inter-App Audio.

4. AKAudioUnitManager was removed. A project to demonstrate this functionality has been started here.

5. AKMetronome has been removed. Its easy enough to create a metronome with Sequencer and one track. This will be demonstrated in the Cookbook examples project.

Significantly Changed in v5

The following items have been very significantly changed, even if their names are similar:

1. AudioKit 4's file managing class AKAudioFile has been removed. We have found Apple's AVAudioFile sufficient for this purpose now. Format conversion is now handled by AudioKit 5's FormatConverter.

2. AudioKit' 4's audio player AKPlayer and its associated AKDynamicPlayer and AKAbstractPlayer have all been removed. In its place we have AudioPlayer which is simpler.

3. The following taps have been removed: AKLazyTap, AKRenderTap and AKTimelineTap. Instead, we have traditional AVAudioEngine style taps: AmplitudeTap, PitchTap, and RawDataTap.

Minor Changes in v5

Next we have things that are different but rather trivial to reimplement (and very worthwhile to do so).

1. The best way to use AudioKit 5 is to use Swift Package Manager. If you're hooked on Cocoapods, we still plan to provide Cocoapod versions, but we strongly encourage you to move to SPM. We have, and we do not regret it.

2. AudioKitUI is now a separate package that has AudioKit as a dependency.

3. The AudioKit singleton no longer exists so instead of writing

AudioKit.output = something
AudioKit.start()
AudioKit.stop()

you'll need to create an instance of an AudioKit Engine:

let engine = AudioEngine()
engine.output = something
engine.start()
engine.stop()

4. AudioKit 5 drops the AK prefix from class names.

If you get errors like Cannot find AKOscillator in scope try Oscillator instead. If you already have defined an Oscillator class in your project, you can access AudioKit's oscillator with AudioKit.Oscillator.

5. AudioKit 5 effects no longer take optional nodes on initialization.

In AudioKit 4 you could write AKReverb() but now you will have to write Reverb(nodeYouWantToReverberate). One of the main reasons for this is that our audio engine is keeping track of the connections and now tightly enforces that you're not making any mistakes with dangling nodes not properly connected.

A side effect of this change is that the syntactical sugar of setting up your chain after initialization with the syntax oscillator >>> reverb is gone. To change your signal chain, even while the engine is running, use a Mixer and its addInput and removeInput methods.

6. Ramp duration is no longer a property of AudioKit or even on AudioKit nodes. Instead, ramping parameters is much more flexible. What used to be:

oscillator.rampDuration = 0.2
oscillator.amplitude = 0.9 // ramp to 0.9 over 0.2 seconds
oscillator.frequency = 880 // ramp to 880 over 0.2 seconds

is much more flexible:

oscillator.$amplitude.ramp(to: 0.9, duration: 1.2)
oscillator.$frequency.ramp(to: 880, duration: 1.7)

Notice how ramping duration is independent for each parameter. And notice the parameter is a property wrapper in this case, so it is prefixed by the dollar sign. Setting parameters like in the first code still works, but the changes are immediate, not ramped.

7. In addition to all parameters on AudioKit nodes (except for the ones based off of Apple DSP) being rampable, they are also automatable. By generating piecewise linear curves, you can approximate all kinds of ramp curves or other time varying changes to the parameters.

8. Microphone access has changed. There is no more AKMicrophone and instead you create a microphone as an AudioEngine.InputNode and instantiate on an engine you create:

let engine = AudioEngine()
let mic: AudioEngine.InputNode

init() {
    mic = engine.input
}

Also, AKMicrophoneTracker was removed. Using an AudioEngine's InputNode along with a PitchTap is a better solution.

9. All of the projects in the Examples for have been moved out of this repository. See the Examples documentary for links to the new repositories.

v4-v5 Class Name Changes