You could try looking up engineering papers
Best wishes on getting the info you seek around this subject.
or
The line array box was also tested in a controlled environment to verify its performance. The results of the testing showed that the line array box was able to achieve a maximum SPL of 125 dB and a frequency response of 50 Hz - 18 kHz.
Or manufacturer's data on loudspeaker systems 12 inch line array box design pdf
The design of the line array box was simulated using a combination of finite element analysis and boundary element analysis. The results of the simulation showed that the design was able to achieve a flat frequency response and a wide coverage pattern.
Here is a sample PDF of the design:
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