AFMG Network Forum

Justin · Member

I find that when doing a "Find Impacts" Ray trace, my results show either a plateau or decrease in the final orders of impacts per order.

The tutorial suggests that this is a poor/inaccurate ray trace and that I need to modify the number of orders and rays/loudspeaker to correct this.

Is there a general rule of thumb as to how many reflection orders and Rays/speaker I should be using so that I can avoid days of guess and check work?

The room I'm tracing is a medium sized theater. I started with using 10 orders and 200k rays/speaker.

Stefan · Member

Hi Justin,

we generally recommend using a time cut-off instead of an order cut-off. You can then use Predict Impacts which is a much more stable method to add a statistical tail than Add Random Tail.

If you use time cut-off instead of order cut-off, you can utilize Impact Chance as a quality criterion. A chance of 80% and higher is recommended.

Please notice that the raytracing methods in EASE can only provide a partial answer, as they leave out crucial effects like scattering and require adding a somewhat arbitrary, estimated tail. Please use the AURA module for more advanced studies.

In AURA, most of the calculation parameters provide useful defaults based on the size of the room and its acoustic properties. Nowadays we recommend the regular raytracing methods be used for 3D reflection analysis rather than for auralisation.

Stefan