15 vs 18
 

ok, give me your opinion on my situation here
im looking at whether i should get a 15 inch or 18 inch sub
it will be the Fi BL series and its going into a 2009 Scion xB
i will be pushing 1200 watts rms
the 18 recommends a box between 5 and 10 cubic ft after port,
the max i think i will be able to give will be between 5.5 and 6.5 ft after port

the 15 recommends between 2.4 and 4 ft, and i would definitely be able to fit that.

so what do you guys think, a slightly choked 18 or a 15?

go take your measurements so you aren't guesstimating.
a friend of mine off ssa had 2 15" bl's off a saz3kd in a lincoln town car, and that thing slammed and sounded so good, i wouldnt have mind having them. but i had my 12" ssd in my truck and it was loud enough, but i just went over the top and ordered me a fully loaded 18" btl, and sometime next week i should have my saz3kd.

go for the 15 though imo.

how did i know you would be the first to respond to this? ya 15 would work better since you will be givin it proper airspace

2 12s. More output AND better SQ.

thought the post didnt come up, check below

that btl is gonna be insane. i wish i had the money to do a setup like that
but do you really think the 15 would be louder? im really mostly looking for SPL (unless the 18 would sound like butthole in a small box)

msall
right now money is an issue.
the 18 would only be $310, and the 15 even cheaper....and an 18 is bigger than 2 12's.
but what 12's would you recommend that run 500-600 rms?
like i said, im mostly looking for output here, without it sounding like the audible representation of a crusty piece of dog *****

for output, get the btl, its fi's most efficient subwoofer, that is if you want to go with fi's brand, if not, ssa icon is about to come out and its a beast. sundown niteshade 12 or 15 would work out for you.
what amp are you going to be using?

yeah, even off the 1000~watts its seeing right now, its pretty insane, i just cant wait to get it off this crapfonics and let it see a real amp, i just need to get some kinetic batteries so it has a power source to draw from.

you have an HO alternator?

A single 15 in a sealed box, juiced up right could give amazing output AND sound clean.

I would love to run a 15...maybe someday I will instead of my 2 12s... (Done 3 12s in the past, single 12, and 2 10s).

why would you go from 2 12's to a 15?
2 12's have more surface area
thats partly why i want to go with the 18, cause if i do a 15, i might as well do 2 12's....but everyone has 2 12's and i want to try to do something unique

yeah, thats why i did a 18" dont know anyone around my area running a 18 in a truck!
and no sir, just stock 130 amp alt. i think it'll hold up fine if i add like 4 big batteries and some runs of 0 gauge

Orion d2400
1200rms
Fi definitely is doing it for me with the prices. i would rather give the full power to a BL than half the power to a BTL, i dont want to risk clipping my amp

i would look into a HO alternator. i got mine done in my truck for 200 bucks at a local shop. 200 amps.

not bad at what ohm though? is it 1 ohm stable?

yeah, full power to a sub then underpowering it, but still you cant clip a amp, you can clip a speaker though, but thats if you dont set your gains right, only thing you really need to mess with on a amp to avoid clipping it is.
-gain
-ssf (if you're doing a ported box)
-lpf
thats about it, leave bass boost alone and you'll be fine.

i have the btl on my hifonics bxi1206d and its playing just fine. im not even giving it suggested power and it slams for what it is. everyone says underpowering a speaker is bad for it, no thats nowhere near correct, only reason why people say that is because they go out and mess with their gains and try to get it to sound as loud as possible which ends up being bass boost all the way up, gain all the way up, and bass on the h/u all the way up, that leads to a clipped signal and there goes their sub they just spent all their money on.

yea, its 1 ohm
i didnt "properly" set my gain, but i have it at about 50%, on the HU: -1 for bass, +2 or 3 for sub