Right now I have Q-Logic bandpass box in my car with a Audiobahn AW1200Q 12" sub. The box has .98 cubic feet internal volume (ported section), .84 cubic feet internal volume (sealed section). My question is, sense my sub requires .7 - 1.63 cubic feet of internal volume for a sealed box, could I cut the sealed sections off, fill in the ports, and use the box that way. Also should I stuff the box with poly-fill when finished? I have never heard a good solid yes or no to poly-fill.

 

Does anyone know?

Bump

 

You could, and it would sound better. (provided you did a good job sealing it off)

And before you bump your own posts, could you give us more than 14 mins?

 

Sorry, I am not good at waiting. I was going to try it tonight, but if it is zero degrees out tonight it can wait.

 

I braved the cold last night and did as I planned. Everything went well seperating the sealed part from the ported part. In ordered to seal the ports off, I cut a piece of partical board to fit the length and width of the top of the box. Next I glued and screwed the piece into place. From inside the box, I put construction grade caulk around the port holes to totally finish the seal. I also fab up a amp rack and mounted it the box to free up more trunk space. Next I need to recarpet the box and I will be done. After everything sets up and it warms up a little outside, I will reinstall everything and hope everything sounds better.

 

.84 is very close to min. As long as you have a strong amp it should be fine.

 

you should've used 3/4 MDF wood instead of particle board. that board is very poreous and will flex when the sub hits. Also, remember the more cubic feet of air you have inside a sealed box, the more free and lose the sub will hit. this means that if you have a weak amp pushing minimum cu.ft = poor sound. but if you have a strong amp pushing too much cu.ft = wobble and distortion. Q-logic had engineered that box and you should've kept it the way it was made. if you need more or less air volume, you should've made or bought a new box. my $0.02

 

It sounds fine. I park about 20 feet from my house, and my wife was complaining that I was shaking everything in the house. I'm happy for now until I get bored with it again.

As for using MDF over partical board. I had some partical board laying around my house. I was trying to do this without spending any money.

 

HA! HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA HAHAHAHAHA!

Q logic boxes aren't engineered to be the best for each individual sub. They're made to fit most subs. It's a crappy pre-fab box. Yes, they're expensive. Yes, they save a lot of work. Are they good? no.

An enclosure should be designed for a specific driver. Not to fit the most common 50-80 drivers on the market. This is why prefab boxes will always be outperformed by hand made custom designed boxes.

Bravo on your box mod, HKL. Now, all you need to do is make a new box, from scratch (I'd reccomend about 1.25ft^3, sealed, stuffed with about a pound of poly fill). You'll be glad you did.

 

I am already starting plans to build a 2.024 cu/ft ported box. I have all the measurements figured out. I am just working out a few ideas that I have for the box. I am thinking of using a piece of plexi-glass ( if I can find a piece thick enough) to mount the sub on and building the rest of the box out of mdf.