So I finally got my boxes built (2' x 6') and just need to finish the assembly. They are roughly 9" deep at the top and 3" deep at the bottom. I plan to mount 2"-4" of 703 Insulation, suspended an inch off of the back panel, sealing the boxes and mounting these about two inches off the wall (side walls). There will be (12) of these total (six each side l/r). Are there some tricks I could utilize to broaden there usefulness? I have seen people mention ports. Maybe port every other one? All of them? Suggestions on port size/type? Different material for absorption?
I intend to do ceiling treatments that will be more targeted to problem areas, once we analyze the room. These will not be covered with fabric. They will be exposed wood, stained with trimmed corners.
I have seen people mention ports. Maybe port every other one? All of them? Suggestions on port size/type?
Do you want to tune them to a specific frequency with a port? I am on the wrong computer to pull up my archive, but I have a reference for a calculator for a ported panel-faced enclosure that's sort of like this:
In practice, it is typical to buy a longer port tube than you need, then during testing, cut its length sequentially until you get the required tuning. OTOH, if you want this to function as a pressure-based absorber, I'm pretty sure it needs to be air tight. If you want this to function like a Helmholtz absorber, search GS for Boggy's ported HH design. I just don't have time right now.