AFMG Network Forum

ChrisH · Member

Hi

I don't know how well EASE is suited to modelling outdoor sound systems, but I have a discrepancy when modelling over long distances with the RT locked at 0 seconds. An old version of EASE (v4.0.0.30) shows direct SPL being exactly the same as total, which is what I would expect with no RT. However, on a later version (v4.1.0.7) total SPL is always higher than direct; it almost looks as if there is an RT value set, but there isn't. Can anyone explain?

Thanks!
Chris

Stefan · Member

Chris,

this needs some comments.

First, to model outdoor applications, use the setting "Room Open" and set the Room Volume to 0. Otherwise EASE will assume that you want to work with a kind of reverberant space.

Second, note that measures like TotalSPL and D/R are statistical in nature, so the Interference setting does not apply to them. If you calculate the Direct Sound with Interference Off you should see the same values for Direct and Total, though.

In EASE 4.2 we will try to make this situation clearer, with explicit switches for outdoor / indoor applications.

Stefan

ChrisH · Member

Thanks Stefan, that's a bit clearer now.

However...this leads to my next awkward question - what is the situation in Aura, where I don't think you can map with an open room? I have tried modelling the sound breakout from an open-ended building, but Aura predicts a similar RT in the indoor and outdoor areas even though all outer faces are set as absorbers! I want to know the total SPLs due to reflections alone when direct line of sight is blocked, but can't be sure of them when the RT looks wrong.

Cheers
Chris

Peter Patrick · Member

Hello Chris,I'm not Stefan but I believe you might try AURA mapping to a seat or the probe from the EYES module. (Tools - Calculate AURA Response) If you don't like the answer try the original style ray tracing which will show you the reflection paths.

Hope this helps.
Best
P.J.P.