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-   -   Is it possible to use the data output from REW to locate the Schroeder frequency? (https://www.gearslutz.com/board/studio-building-acoustics/1282948-possible-use-data-output-rew-locate-schroeder-frequency.html)

logjamparty 13th October 2019 05:20 PM

Is it possible to use the data output from REW to locate the Schroeder frequency?
 
I've calculated the theoretical Schroeder frequency in my room. But I was reading online this morning (always a bad idea) and came across this scholarly article from 2017.https://www.mediterraneanacoustics.c..._at2_final.pdf

It concludes "...the use of the Schroeder Cutoff Frequency in small rooms should be exercised with some degree of caution, as it this use challenges some of the fundamental theory behind Schroeder’s equation. It is important to note the underlying condition for Schroeder’s theory of a diffuse, isotropic reverberant field. This condition is perhaps never perfectly met, but it is much more difficult to achieve in a small room than in a building as large as a concert hall. Also of concern, and perhaps debate, is whether or not the decay measured in a
small room then qualifies as reverberation."

As with all theoretical calculations in acoustics, things change once you actually get in the room. So I was curious if there was a way to use REW to find a more exact Schroeder Cutoff.

dinococcus 13th October 2019 06:43 PM

Quote:

Originally Posted by logjamparty (Post 14263293)
I've calculated the theoretical Schroeder frequency in my room. But I was reading online this morning (always a bad idea) and came across this scholarly article from 2017.https://www.mediterraneanacoustics.c..._at2_final.pdf

It concludes "...the use of the Schroeder Cutoff Frequency in small rooms should be exercised with some degree of caution, as it this use challenges some of the fundamental theory behind Schroeder’s equation. It is important to note the underlying condition for Schroeder’s theory of a diffuse, isotropic reverberant field. This condition is perhaps never perfectly met, but it is much more difficult to achieve in a small room than in a building as large as a concert hall. Also of concern, and perhaps debate, is whether or not the decay measured in a
small room then qualifies as reverberation."

As with all theoretical calculations in acoustics, things change once you actually get in the room. So I was curious if there was a way to use REW to find a more exact Schroeder Cutoff.

Hello,

IMHO, In a little room, instead of the Schroeder frequency, We could speak about the Transition frequency interval.

The notion of reverberation in a little room has been discussed on gearslutz. Maybe we can avoid resuscitating a conflict.

Soundman2020 14th October 2019 04:13 AM

And adding to what dinococcus said: Schroeder is not really a "cut off" at all! At best, it's the spot in the middle of a range of frequencies, maybe a couple of octaves wide. Its not that everything above Schroeder is wonderfully smooth modal response all the way up to heaven, and everything below that is terribly bad major modal resonance all the way down to hell! The Schroeder frequency is a theoretical calculation based on several assumptions that may or may not be true. It serves as a guide to roughly where things transition from one type of acoustic response to another, but it's a broad transition, not sharp... and that's about it! In a typical small room, that's about all it can tell you...

But to answer your question: You probably can't calculate it from REW, but you can often see the effects in the REW graphs. Well below Schroeder, you see the huge ugly peaks and dips of bad modal stuff, with well defined sharp resonant tails, and wildly different decay times. Well above Schroeder, things look a lot smoother, with only minor peaks / dips, and more even decay times. Once again, it's interesting to look at, where you can sort of estimate "Shcroeder must be around the middle of that transition region in my room, say roughly XYZ Hz."... but that's about it. Its not much use beyond that. The treatment you put in your room won't be change much, of your Schroeder frequency happens to be 50 Hz higher or lower.

Useful in theory for acousticians... but not so much in practice for the average home studio builder.


- Stuart -