Another Porting Question, technical stuff..

[Yedi]

Right now my trunk is all decked out with a carpet kit, sound deadening in the decklid ( polyfil stuffing) My box sits on the package tray, fills the whole thing, top to bottom side to side, I have 2 MTX 8000 12's ( 2300x amp 750 watts) in there mounted on the outside ( magnets stick out) and also polyfil stuffing in the box. with this set up it sounded best. The box is sealed, and the low low bass is awesome, just the mid bass and the punch could be more. Could porting this box help me out? leave the polyfil in or not when porting? What is the formula for finding the port size for your box?


If you need any pics I can send you some, any help would be awesome...

 

[Gbodyolds]

i had the same problem with my box when i mounted it up on the shelf then i figured out that if the trunk is open the problem goes away. i was told the trunk is too sealed and that it kind of sufficates the subs dont know if this makes any sence but its what i was told and it works

 

[Dr. Jeckel]

About 8 years ago I got a little book on speaker box building from radio shack and it told you everything from porting to enclosure volumes .....everything you would have questions on. The larger the box the less power you need to power the sub(up to a certain point then it just sounds bad). Most 12" subs need 1.25 cu. ft. sealed per sub. Matting material on the inside increases the virtual volume slightly. You may not be giving the subs enough space. Sealed boxes are greatly for deep clean bass and band pass or ported are better for booming bass. It all depends on what kinda music you like to how you setup your system.
If you adjust your frequency crossover higher you can get some more punch to the bass as it will allow the reproduction of higher frequency bass. It all depends on how you match your rms power of your amp to your subs and what kinda bass reproduction you want. I have a single 12" MTX 6000 in 1.3 cu.ft and my box takes up 18" side to side of the whole shelf. Was your box custom built for the subs? Anyways...I would get the book and just play with the settings on the amp some.