Determing the amplitude of an audio signal by
outputting the value of a generator node into the AKAmplitudeTracker.
This node is great if you want to build an app that does audio monitoring and analysis.
First lets set up sound source to track
This keeps the playground running so that audio can play for a long time
Experiment with this playground by changing the volume function to a
phasor or another well-known function to see how well the amplitude tracker
can track. Also, you could change the sound source from an oscillator to a
noise generator, or any constant sound source (some things like a physical
model would not work because the output has an envelope to its volume).
Instead of just plotting our results, we could use the value to drive other
sounds or update an app's user interface.