Using Omni-Directional source with REW

[pirola]

Hi!
I'm preparing my university end of studies project and I want to measure the acoustic parameters of a music hall (according to ISO 3382). The idea is to develop a nearly zero-cost solution (obviously not including gear!) so in my search for free/open-source software I stumbled upon REW. I've watched some of the tutorials, read the documentation and some of this forum's threads but haven't found a specific way of setting up REW to use an Omni source, so I want to know if there's sombedoy that already has some experience using an omni source and REW together or if someone has any insight in how I may proceed to set up and use the program.

The omni source the university will lend me is a CESVA FP122 (It comes with propietary software, but only calculates RT60), I will attach the datasheet.

Thank you in advance!

 

[Wayne A. Pflughaupt]

This link includes a video on making RT60 measurements. I don’t see why REW couldn’t be used for measurement instead of the device shown. Hopefully John will weigh in and confirm or correct.

Reverberation Time

Regards,
Wayne

 

[John Mulcahy]

Just set up the omni to accept an external source and feed it the sweep from REW, it's really no different than using REW with any other source. Most of the ISO3382 parameters will be on the RT60 graph for the measurement result, there is a separate graph for Clarity metrics.

 

[Wayne A. Pflughaupt]

John,

Will a sweep will get the same results as a pink noise source, which is recommended in in the link I posted?

Regards,
Wayne

 

[John Mulcahy]

No, they will be better

 

[John Mulcahy]

I want to measure the acoustic parameters of a music hall

When you set the sweep length make sure the overall duration is longer than the expected T60 for the space. A 512k sweep should be sufficient unless the space is very large. On the Analysis preferences, Impulse response calculation section change the truncation setting to keep more of the IR, 9.9 seconds should be plenty.