How much area for sound to exit from downfire box

[Doxquzme Premium Member]

How many in^2 of area do you have for the exit holes under the box? That's what I always look at, just like how you'd design a t-line, based off the Sd of the woofer, somewhat. Like, if you have a total bottom opening surface area that's at least the Sd of the sub or maybe the Sd + port area net, then it sort of shows a relative restriction won't happen, because the bottom of the box has more radiating area than all radiating surfaces of everything in/on the box. That's one way to look at it.

Buck be da (box) MAN!

 

[racin69z]

I am only around 18 square inches on my windows. It appears not nearly enough. I will work on opening it up tonight.

 

[Buck 5,000+ posts]

You can always test it, if that's not too much work pulling it in and out, the box.

 

[Doxquzme Premium Member]

I am only around 18 square inches on my windows. It appears not nearly enough. I will work on opening it up tonight.

I think that if you take out the majority of the surrounding wood using the two corners as legs, you'll be good.

 

[racin69z]

Buck, great idea. I did that tonight, and it actually didn't wheeze like a fat guy trying to run a marathon. I am going to put two windows that match the front 3 on each side and call it for now. Doxquzme, I am sure your plan would work as well, certainly better than what I am going to do. I kind of like the look of the arches. I am far from a SQ guy, I just wanted some bass to go along with the mids and highs.

I am going to have to come up with a good way to hold it down though. It dances around like crazy. I had to lean on it to keep it from rattling. Every box I have ever built was carpeted and either bolted in place or held in with the seat. I bought some adhesive rubber weatherstrip to go under it to help dampen it.

Thanks for all the help and suggestions.