Do I need to deal with Audio Units when I need custom audio effects or can I rely on Audio Queue Services?

Question

From my understanding Audio Queue Services are a higher level API than Audio Units, which use Audio Units. OpenAL also uses Audio Units. So Audio Units is the lowest level audio API in iOS.

I need to record a sound and then apply a custom filter to the audio stream and play it back. Audio Queue Services seem to be good for recording, and they can also be used to play it back. But I'm still uncertain about wether or not they allow to apply own algorithms to the audio stream, like the AURemoteIO audio unit would.