How to emit a custom sound on iPhone

I'm working on a game where a proximity detection for nearby objects will take a great role. I'd like to have it emit a sound when getting close to the obstacle - a sound of a cust开发者_开发问答om tone / volume... I could probably prepare samples of sounds for that, but a custom sound of a custom tone and volume for each of the earphone played.

See the OpenAL wrapper sound manager HERE.

That allows you to set the actual position of the sound, which will affect the volume in a 3 dimensional way.