Mode Calculator Disparities

[thedavidlim]

Hey all,

I've put in my expected room dimensions into both Bob Golds and Amroc calculators and they are giving me different results, sometimes quite different. Specifically, for a room 15.92' x 12' x7.17', Amroc says the Schroeder Frequency is 249hz, while Bob Golds says 129hz! That's a huge difference! The actual modes they report are different as well, but only slightly so, usually within a few tenths of a hertz.

Is one making a mistake, and if so which one?

[Soundman2020]

Schroeder frequency does not depend only on modal response. It also depends on room treatment. So if the room has substantial treatment, then the Schroeder frequency will be significantly lower than the same room with only a small amount of treatment, or no treatment.

Try changing the parameters in one of the models to match the other. The Schroeder frequencies should then be much closer.

- Stuart -

[attaboy_jhb]

I think the Amroc calculator is giving you a Schroeder frequency based on a specific type of room. If you look next to RT60 there is a drop down list and depending on what you select there you get different results for the Schroeder frequency