my main question is, do subs NEED a box? is there a sound quality difference if not? i plan on putting a kenwood amp and two 12inch subs in my car, this seemed like a good idea.
First off you need to know if your subs are meant for free-air, seals, or ported (bandpass) enclosures. Once you know that, THEN you can decide what to build. Free air means the subs are just mounted on something, like most speakers are. Sealed box, is exactly how it sounds. An air tight box that the sub is mounted. Then ported, is simply, a vented box but these can get quite complicated.
I'd recomend looking at the manual for the subs. In it should say what type AND size of box. Or, if you dont't ahve a manual, simply type in the part number in google.
Hope that helps. Oh, and as for sound. I've never heard a free air sub, i'm not sure how they sound. Sealed is very accurate, while ported can be louder.
These require a sealed or ported enclosure
» 12" 4-ohm subwoofer
» five-sided polypropylene cone with foamed rubber surround
» power range: 90-380 watts RMS (1,300 watts peak power)
» frequency response: 18-2,000 Hz
» sensitivity: 89 dB
» top-mount depth: 5-5/16"
» sealed box volume: 1.15 cubic feet
» ported box volume: 0.82 cubic feet
I would question there reccomended box specs also and am guessing they have it backwards as ported reccomendations are always larger than sealed reccomendations.
666raCing wrote:so is there no way that i can do these things free-falling? I really dont want to construct a box if i dont have to...
Well sure you can run them free air however they will sound like garbage and most likely eventually will detonate or unload. Basically taking a sub that is designed for a box and running it freeair is like tuning a ported box for 60hz and playing musical content in the 40 hz range. The speaker literally unloads itself and breaks, ETC it reaches the end of its excursion capabilities.
Also after a little research it appears that the box volume specs are actually correct which is odd but after some research it appears the subs do best in a sealed enclosure.