The listener object is usually the player sprite. You place the positioned audio on the object where you want the sound to come from. For example, if you have an explosion, you can place the sound to the explosion. Then the closer the listener object (player) is to the explosion, the louder it will be. Of course it's not just the volume, if the explosion is to the right of the player, it will be heard in the right speaker etc.
Edit: By the way, there's an example capx that comes with construct 2 in the example files. If you haven't already, you might want to take a look at it.
Oh i see, thanks for that - But, i just want the sound to be louder or lesser depending if ur close or not. For example rain-sound to be louder if ur closer to the window, and lesser if u walk away from it, but the listener doesnt seem to do anything.
Also its not about right or left speaker, its just about the how loud it plays when ur closer. No matter what i do or how i follow the tutorial, the sound/music plays at same height.