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blackdrag450r
05-12-2010, 10:01 PM
i'm looking to put 2 1000watt 12"s in a ported box tuned to 33hz in the trunk of my grand am, i'm going to build the box myself but i have never built a ported box before. would i need bracing?
each sub needs 1.75 after displacement. But it will be more to account for the port right?
max dimensions
L: 37.5
W: 18
H: 14
thanks

SCcobra4me
05-12-2010, 10:56 PM
You should be fine but if you wanted to separate the box it wouldn't hurt, making two separate ported chambers.

mazdakid
05-12-2010, 11:02 PM
Yes you will need to add more space for the port and for subs displacement. Id atleast use a brace from top to bottom in the middle of the box.

blackdrag450r
05-12-2010, 11:06 PM
nm

Bumpin' Goalie
05-12-2010, 11:08 PM
what if I build two boxes instead and connect them once in the car, this would be alot easier to get it into the trunk, the max dimensions i listed is what my old sealed box was and i had to take the weatherseal off the trunk to get it in! close!

If they are identical, sure. Might not look as good. But if they are secured and IDENTICAL it'd just be like having a single dual chamber box.

Also, aero ports are easy to use if slot ports have you worried.

lilkman2202
05-12-2010, 11:10 PM
where are you at in WI i could help you. PM if you want some help

on1wheel01
05-12-2010, 11:19 PM
simple answer yes. Why not do it right the first time and not regret it later when the box fails. My thoughts if u dont do it right then why do it.

blackdrag450r
05-13-2010, 09:33 AM
is the re box calculator a good one to use??
i spent about an hour doing it last night and got it pretty nailed down....

ascitiesburn69
05-13-2010, 09:38 AM
no.....Its fairly inaccurate.

on1wheel01
05-13-2010, 10:01 AM
It's not to bad. It's ok to use as a general base. I use it and math to figure it all out.

PrestigeSounds
05-13-2010, 10:49 AM
two subs like that should be fine in one enclosure and will be easier for you to construct if its your first time. i agree do it right the first time though. measure twice cut once as they say. a brace from top to bottom wouldnt hurt either.

blackdrag450r
05-13-2010, 12:53 PM
should i make it double baffle?

on1wheel01
05-13-2010, 01:29 PM
What subs r they?

Slo_Ride
05-13-2010, 07:09 PM
Yes to bracing, nothing major, you just dont want the sides to flex. No to double baffle. Yes, you have to subract port volume and sub displacement.
Oh yeah, nice avy. :)

DNick454
05-13-2010, 07:23 PM
Well, I would have to ask this question first... How much power will the subs be seeing, and I mean realistically. Reason I ask is because you stated "two 1000 watt" subwoofers. FYI, subwoofers don't make watts :laugh:

More important is the amp actually feeding them the power. What will that be? And I mean RMS... Because god knows those eGay junk amplifiers floating around with their 2000 watt max ratings and 20 amps worth of fusing are bullshit. For an average pair of 12" woofers in a ported enclosure, bracing will not be needed assuming you use proper box building techniques (straght cuts, wood glue, clamps, pre-drilling, and some screws here and there).
Send me a PM if you have any questions about box design or construction.

Ronny
05-13-2010, 08:33 PM
I brace the hell out of any and all enclosures I make.
That way, you can't go wrong, and you have a really sturdy enclosure for sure.

Blue Fury
05-13-2010, 09:14 PM
Why are some people so unsure about this?

blackdrag450r
05-13-2010, 10:31 PM
2 12" Fi BL running on a AQ 2200
another question i have is with the size range that Fi and most sub mfg. recommend. it says 1.8-2.5 cu ft
if the smallest size is tuned to 30hz and so is the largest size, what are the differences going to be between the different sizes?

Ronny
05-13-2010, 11:15 PM
For every size BL they recommend a 30hz tuning for the best balance of SQ and SPL.
However, enclosure volume for each size woofer is going to differ, as well as port length to obtain proper tuning.
Oh, and btw, brace your box ;) You are going to be running a bit of power, so you will be better off with a solidly braced enclosure.

PrestigeSounds
05-14-2010, 03:21 AM
last time i checked, woofers WERE rated in watts, i dont know who lied to this guy...and with those speakers i would definitely recommend bracing...less flex inside the box equals more output from the box. construction is everything so take your time and do it right.

blackdrag450r
05-14-2010, 09:36 AM
i was merely giving an example on the tuning freq. i was wondering what is the difference between a box 1.8 cu ft tuned to 30hz and one at 2.5 cu ft tuned to 30 hz running the same power??
sound quality difference?? power handling difference??

MONSONwarrior
05-14-2010, 09:40 AM
i was merely giving an example on the tuning freq. i was wondering what is the difference between a box 1.8 cu ft tuned to 30hz and one at 2.5 cu ft tuned to 30 hz running the same power??
sound quality difference?? power handling difference??

Tell me if I'm wrong but a larger enclosure tends to have more output but lose sound quality.

PrestigeSounds
05-15-2010, 03:49 AM
correct...it will play deeper and louder with a larger box but less efficient....not going to be super dramatic in change as far as efficiency so not to worry...

casuxdik
05-15-2010, 03:58 AM
correct...it will play deeper and louder with a larger box but less efficient....not going to be super dramatic in change as far as efficiency so not to worry...

it depends on how much bigger the box is. its not always gonna be louder in a bigger box.

Bumpin' Goalie
05-15-2010, 03:59 AM
correct...it will play deeper and louder with a larger box but less efficient....not going to be super dramatic in change as far as efficiency so not to worry...

Larger box usually equals more efficiency :) that's how it is able to get deeper and lower. It can reduce the mechanical limitations though if you go overboard with it.

PrestigeSounds
05-15-2010, 04:39 AM
by less efficient, i was referring to being able to hit all frequencies accurately....but still correct me if im wrong...always open to suggestions and corrections

Bumpin' Goalie
05-15-2010, 12:35 PM
by less efficient, i was referring to being able to hit all frequencies accurately....but still correct me if im wrong...always open to suggestions and corrections

With ported boxes, the larger they are, the more drastic the peak around tuning. So that would be correct. :)

sulin's baby
05-15-2010, 10:14 PM
its also true the bigger the box the easier it is to blow the sub

blackdrag450r
05-17-2010, 09:36 AM
alright, well i changed direction on this build, i'm going with 1 12" BTL. the room that i had in the trunk wasn't enough to put 2 12"s in and have them be efficient enough in the box size... plus i couldn't afford 2 of them! haha
if the range for one btl is 1.8-2.5 what size should i go with? anyone have any experience with the btl's?
thanks for all the replies.

on1wheel01
05-17-2010, 10:15 AM
around 2.2 would be good. thats what i had my cascade omega in

Ronny
05-17-2010, 12:41 PM
Give the BTL 2.5cubes net @ 35hz and you'll be golden

blackdrag450r
05-17-2010, 02:34 PM
Give the BTL 2.5cubes net @ 35hz and you'll be golden

does net mean before displacement??
35hz is pretty musical?? it recommends 32-33 on their site, is it that big of a difference?
thanks

PrestigeSounds
05-17-2010, 03:12 PM
wont be a HUGE difference but it will make a difference