9 replies to this topic

[monster_mini]

hi,

i am currently in the process of buying a 12 inch JL sub and kenwood amp:)

i beleive they are rated at 800watts peak power, so my questions are

1. will my standard alternater be able to cope with this?

2. i have made my own boot board kit which fits nicely, but its all fitted together with just tightness between the panels, theres no actual brackets or screws, and i wanted to put the sub in the right hand side(where you would normally put a right hand tank, and do you think the sub would just be to heavy and once on it would fall out?

3. how important is it to make a sealed encloser for the sub?

thanks

[carts60]

Your alternator should be able to cope fine. Iv got a 1000W amp powering my subs and a 400W one for the speakers and iv not had any problems yet - even when the sounds really cranked and the whole cars wobbling with bass.

I have serious doubts whether you'll be able to fit a 12" into the boot kit without some form or solid fixings. My boot kit doesnt stay together even when its only got iteslf to look after, let alone a sub.

It shouldnt be too hard to knock up an MDF enclosure for it though, or to make the right hand panel more secure so it doesnt just disintegrate with the vibrations.

Its not important to seal the enclosure. The recommended volume will change though depending on whether the sub is mounted in a sealed or unsealed enclosure. What you're doing is called 'Free Airing' the sub, because you're simply fitting the sub in place without a real box which it sits in. This is fine too, just make sure the sub you get is OK to be free aired. JL subs should be fine to be honest. I had one and it was immense so you shouldn't have any problems. The only difference between sealed and unsealed is sound. Unsealed give what i would describe as more wobbly bass where as sealed enclosures give a more kicky sound in my opinion.

[monster_mini]

ok thanks:)

how big would the enclosure need to be for a 12 inch sub??

[Carlzilla]

Standard alternator should be fine, but i have a 70a one just for peace of mind

Sealed Enclosure is the best way to go in my opinion, make sure you have around 1 cubic foot of volume in the enclousure, else the sub is gonna sound really really dodgy, i bought a pre made lining kit, and had to enlarge the enclosure to suit the sub. when the box is built go around the joins on the inside with silicone sealant, otherwise air will escape from the enclosure and it makes a farty noise

But you can port the enclosure, but they take up more room as they need more volume yet compared to a sealed enclosure. id find out the manufacturers reccomended volume and try to match that though, use my 1 cubic foot as a guide if you cant find anything. Free aired subs (if you have one) dont need an enclosure, but free airing a sub which isnt supposed to be free aired wont sound very good, or do the sub any favours.

http://www.theminifo...howtopic=161634

Thats my thread on it if you want to check it out.

Hope that helps, and Have fun

[minilester]

ok thanks:)

how big would the enclosure need to be for a 12 inch sub??

1CUBIC FOOT!

im in the process of trying to build a box for a 12" sub at the mo... and it is complex trying to keep room and prevent rattling...

[Carlzilla]

lester, check out my thread too if you dont have a washer bottle in the boot

use some egg crate foam or similar inside the enclosure, acoustic wadding is the proper stuff for the job though. it helps dampen out high frequencies emitted by the sub, which are generally the ones who make the disgusting rattles in the boot

[monster_mini]

ok sweeeeeeet:)

thanks

[monster_mini]

should i put anything in the sub box? and what effect would different things give?

thanks:)

sorry for been useless:)

[Carlzilla]

i used foam, or you can use acoustic wadding, as i said it dampens the higher frequencies and gave me deeper clearer bass for the sake of lining my enclosure with it, pretty happy with that

[pbrain]

if you don't intend to remove the box afterwards, i used expanding foam around the box to keep it tight & stable. You can use this with a combination of roof sealing tape & silicone to go around the car & eliminate rattles & noise. You hear loads of cars with sweet systems, but rattling boot lids just kills it.