for a 12" single woofer ,is there any restriction on the size of sealed box you can put it in. i bought a q max box with a 12 inch kenwood woofer however im building an enclosure in the boot and im wondering if the larger the box the better the sound?
or would it be better to have 2 woofers in the boot instead of one?i want to run my box from the back seat to about where the wheel arches finish and as high as the hinge point of the boot. any helps great.

 

follow the smallest measurements with the sub instructions. on sealed boxes you want them small. you can larger if you want a ported box but ported boxes sound too boomy for some people so it's up to you on box choice. my preference would be sealed. some of the best sounding home speakers are sealed enclosures. Remember the Infinity Reference Standard 5's? $100,000/pair back in 1989!!

 

i do want a sealed box .the on ive got now for the woofer is 500mm x 450mm x420mm. but i want to make one thats 1000mm x 450mmx x 420mm.is it pointless doing this with 1 woofer in it and will it sound better or worse.

just wanna know before i buy another 4ch amp

 

dude,
get a sealed Q logic box and then stuff it w/ couple pounds of polyfill. It'll sit snug in the spare well like mine.

 

i would just follow the spec sheet on the sub for a sealed enclosure. if u go too big ona sealed box with a single sub, it'll sound hollow (unless it's a 15")

 

it sounds like you're willing to give up some room. do yourself a favor, and read the jlaudio tutorials on box design.

I'll agree w/housedj on the sealed enclosures for midrange drivers, as those infinity 5's are. as for sub-bass though, some of the best sounding elcosures are ported. only real good sealed home sub I remember seeing was a velodyne 18"... 99% of all high end home subs are in a well designed, well constructed ported enclosure.

the reason ported enclosures get such a bad name in the car audio world, is that companies are mass producing poorly designed, poorly built enclosures, and they expect any woofer to just drop in and sound good.

an enclosure should be designed around the woofer, on an individual basis. I won't go into more details on this part.

a ported enclosure is typically 3db louder, because it is activly using the backwave of the woofer. a sealed box just uses the front wave and "tries" to cancel out the back. a ported design also doesn't put any strain on the woofer, therefore the excursion is very little around the tuning frequency, therefore the woofer will have a very quick transient response. = much better suited where true sound quality is desired.

also, in an spl, since the cone is moving very little around the tuning frequency, tuning the enclosure to the car's resonant frequency, will allow the user to play a linear note at the car's/enclosure's tuning frequency, they can add a very large amount of power to the woofer, without overexerting, or distorting the woofer. the only issue that comes into play at that point is thermal capabilities of the woofer's voice coil(s)

to sum it all up, spend some time, research, and design yourself a ported box, and your 1 woofer, will play cleaner and produce higher spl levels, then 2 woofers in a sealed box.

 

i like sound of doing some porting. can you post the jl thread for me?

 

http://www.jlaudio.com/tutorials/index.html

read, read, and be educated... come back to me when you seek even more knowledge