AFMG Network Forum

micko_v · Member

Hi guys,

I don't know if this is normal, but for example, in every receiving point in the audience area I have an average of 85dB, max 89, min 83dB in the frequency Total SPL area, graph and table.
http://prntscr.com/l5wvgo

In the map area I have Total SPL min 96dB - max 98 dB.
http://prntscr.com/l5wvq6

How can I map an average SPL for audience area, and why the total spl is different?

My goal is to set average SPL in every point 85dB, which I do. But on the mapping area i read this higher values 96-96dB. Why is that? What is summing, and what is the point of summing? Usually when I measure Leq in various points in closed space, I'm doing log average of every measure point, I'm not summing every receiver point in the audience...

Please help!

AFMG Frank Siegmann · Member

Hi Micko,

please note that the average SPL is the average value for all calculation (receiving) points. So there is only one value per frequency band per area.

To check then differences you get we would need your EASE project. If possible please send it to support@afmg.eu .

Frank Siegmann
AFMG

Peter Patrick · Member

Hi Micko,
If you observe the graph you will see there are roughly 13 1/3 octave bands from 250 hz to 4 KHz at around 80 to 85 dB(A). If you do a power sum on those you will undoubtedly end up with the numbers showing on the mapping plot which is the sum of all the 1/3 octave bands in the graph.
The graph is a frequency vs SPL plot and the mapping plot shows the combined total which is what you asked for when you set the mapping parameters.