ARE 5.0 - Acoustic Formula a = SAC x S

How to solve the a = SAC X S formula for acoustic questions on the ARE 5.0.
This video is from my ARE 5.0 PPD and PDD Study Assignment Course: hyperfinearchi...
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hyperfinearchi...

[@st0laf108]

The NRC is calculated as the average of the 4 frequency bands from 250-2000Hz. I believe this is standard for all NRC averages.

[@vergoregiste5300]

Thank you B en.

[@daphnechai453]

I was wondering why some NRC>1. Found this "Long ago, a man named Sabin found that some mysterious material was the best absorber known to man (maybe it was lambs wool) and they called this NRC 1.00 as this was the best known absorber at the time. As time went on, other materials were discovered to have a better NRC so the numbers had to grow.
Hence we find NRC numbers greater than 1.00."

[@_username___]

Very helpful!

[@qsayeeda]

Audio is not good.

[@HyperfineArchitecture]

Try listening in a room with a higher Sound Absorption Coefficient