My app plays audio files with AVAudioPlayer, and I've used most of its methods and properties to build a playback control interface with buttons to play/pause, seek, etc. Now I want to add a pitch-shift feature using the new AVAudioUnitTimePitch in iOS 8. I've found the sample code in this question and it works when I run it, but it uses AVAudioPlayerNode instead of AVAudioPlayer.
Is there any way to connect an AVAudioPlayer to an AVAudioEngine, instead of the AVAudioPlayerNode? Or is AVAudioPlayerNode completely different from AVAudioPlayer, despite their similar names?
I'm asking because if I have to replace AVAudioPlayer with AVAudioPlayerNode, I'll have to rework most of my control interface to use the different methods and properties available (or not available) in AVAudioPlayerNode.