im starting to build a fiberglass enclosure and im using my spare tire well and the rest of my trunk as well i used a rough estimate that i would have about 2.5 cubic feet but before i build my rings i want to know what would sound better in this area one 15, one 12, or two twelves, its in the back of a dodge neon if that helps any suggestions would be great
i think 2 12" will sound better.
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Shaking The Neighborhood
I'd go with one or two 12's aswell it depends what kind of sound you're going for. The 15 is going to sweep a little deeper for you but usually 12's are a little more accurate. It really depends on your preference and the type/brand of subs you're running. Another option is running a higher quality 12. Many times they'll put out more than either a 15 or 2 12's of poorer quality. I tend to opt for higher quality stuff. it's usually cleaner, louder, and requires less space than running multiple drivers.
you said you have 2.5 cubic feet aire space for the enclosure, so find a sub that able to match the air volume you have, you can go with 1 good 15" that required in the range of 2.5 cuft, or you can go with 2 12" subs that require 1.25cuft each, just make sure you give the sub or subs the volume they need, you can have the best brand out there but if you don't give it the volume it need it will sound like ..... yeah, you know.
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Shaking The Neighborhood
i think your math is a bit off.....i will gaurantee you trunk is larger then 2.5 cubes with out even factoring in the 1.5 cubes of spare tire well...
and like it was said...your music preferences will play a large role in what sounds nice...the smaller the woffer the more accurate and responsive it will be (to me that is what sounds nice, perhaps you like the sloppy play of a 15 or 18) go to your local audio shop and find out what you like to listen too...remember you will be in a huge shop not a car so it will sound different in your car
once you figure out what style of music you like and what you figure it sounds best on ( done at shop, they may even let you play your own cd) you will know exactly how large an enclosure you need...
now depending if you want ported/ vented or sealed. your numbers are again going to be greatly effected...
now do you ant it stupid competition loud or do you want clean SQ? this will also help you chose a driver size and brand.
once you know the above things you can figure out how many drivers you can afford..(like mentioned higher quality drivers will bring premium prices but probably better quality).
know your budget...drivers, amps, spare batteries, wiring kits, sound deadening, (deck and components if you dont have 'em) MDF, fiberglass supplies, primer paint, carpet, vinyl. it adds up in a hurry...full trunk fiberglass enclosure i bet your looking upwards of 400 bucks..
anyway i like 12's and 10's..not together, just in general...you may consider looking into RE (resident engineering) or ED (elemental Designs) for subs
no one should be able to tell you what is nice and not nice...some people swear by Dual, and Legacy, personally i think it is crap, JL is nice but overpriced, i cant stand Kicker, Rocford has served me well in the past, so to has Pheonix gold...MTX fits right in with all the other big box store stuff..now rockford has a big box store line too...LOL crap just keeps falling from the trees...
anyway, only you can tell what sounds nice to you...so go out and listen around...
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Fiberglass Guru.