AFMG Network Forum

andrzejhd · Member

Hi again everyone! In my latest model, I need to simulate large audience area consisting of upholster seating. I found the right material in the EASE database, but it's american and all the coefficients are in sabins/sq ft. Any idea how do I convert it into metric? Or is it somehow done automatically by the program?

Thanks for help,
A. Rolling Eyes

Waldemar · Member

Hi,
to obtain the absorption coefficient (alpha) of the material (which is used in the EASE material database) you have to know the total surface (S) of the measured object.
alpha = Sabine / S
If the Sabine-value is in imperial units (sq ft) then the surface S must be in sq ft also.
If there are no different data for the used octaves, use the same value for all octaves.

andrzejhd · Member

My question was rather how to reverse-engineer the absorption coefficients from imperial to metric. Is it even possible?

I don't get what you mean here:
"If there are no different data for the used octaves, use the same value for all octaves."
EASE database coefficients are usually 1/3 octave values ^^

Have a great day,
A.

thomas · Member

andrzejhd · Member

Thank you Thomas... That's what I thought from the very beginning! Now I understand my mistake - as you correctly pointed out - alfa is unit-less.

Thanks again,
A.