Understanding Source Directivity

[Tommy Burn]

Hi All, 

I'm having some issues understanding the Speaker Directivity in I-Simpa. I can get a directive source using the Directivity Balloon option, and setting the X,Y and Z numbers, however I'm not sure what these numbers refer too. 

I understand that, for example, if I increase Direction X to 5, the arrow increases in the X axis by 5 meters, and a surface receiver shows an increase of source levels in that direction, however I need to simulate a speaker and I'm not sure how to choose the correct number.

I also noticed the Directivity Balloon option has three different speaker options (spk1, spk2 and spk3). What are these, and is there a polar plot showing how they are different please?

Many thanks.

Tommy

[Nicolas Nico]

Hi,

The X,Y and Z define an euclidean vector, it only define a direction for the sound source.

Directivity files are stored in I-SIMPA\Directivities folder. The file format Ease ASCII File Format http://ease.afmg.eu/dir_dnl/speakerformats404.zip

I-Simpa can not plot directivity files currently.

[Tommy Burn]

I understand. Thanks very much.