panel absorber

[genelec79]

Hi guys. I have buy some material today and i wanna tommorow to make 2 perforated panel absorbers for my small control room. So i have found some calculator on the web (for tuning the panel) but i dont understand that perforation percentage . Over there in formula was everything clear (the number of holes for specific frequency,the depth of the box and...
sORRY IT WAS tiping mistake. So over there in formula was ---FOR SPECIFIC FREQUENCY I NEED TO MAKE 50 HOLES IN THE PANEL WITH 0.39 PERCENTAGE OF PERFORATION .


Concrete question is--can i just split the panel area in 50 equal pieces and make holes inside,,or i need to make it on different way (cause I dont get it that percentage of perforation)? THANKS FOR THE ANSWER!

[spm_gl]

Simple, the perforation perentage is the amount of area the holes have, in relation to the total area.
Say you have 1m² panel. You drill 100 holes, 10mm diameter. The area of each hole is PI*r², approx 0,8cm², makes 800cm² holes to 1m² panel, is 8% perforation percentage.

[spm_gl]

To answer your concrete question, yes, you can (and should) view the panel as 50 separate pieces. Then your single hole area must be 0.39 percent of the area of the piece.

[genelec79]

Hi guys. I was lillte sleepy yeterday when i wrote previous post!!! In this calculator for the Panel absorber i was able to fill all of this datas (panel 1 m2,depth the space behind 35 cm ,diameter of holes 1 cm, amount of holes 50 and than the calculator shows me that target frequency for this combination is 40 HZ WITH PERFORATION PERCENTAGE 0.39. So does this play any important role(perforation percentage of 0.39),cause i allready tipe the number of holes,OR IS IT JUST A CALCULATION OF MY DATAS?? THANKS GUYS FOR SUPPORT!