Setting correct volume / distances

I’m quite a newbie on JOAL, but I’ve managed to setup an active sounds for my avatars (cars) and scenegraph. Currently things seem to work pretty nice, except the sound volumes are not correct relating to listener<–>soundsource distances.

I’m using odejava for the physics part and simply updating listeners position and object’s positions / velocities per each step. Of course they are not directly compatible, amazingly they work for my case even this good.

Ok, now to the question:
Visually, if I’m about ten meters away from my car, I hear extremely little of the engine sounds, but if I’m just above the car then I can hear the engine sound nicely.

What is the correct solution? Can I scale the JOAL’s internal coodinates somehow or is the proper solution to multiply all my coordinates by N (e.g. 0.2f) before updating JOAL coordinates for sound sources and listener positions?

Cheers, Jani!