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NoLoud4U
10-30-2012, 08:06 AM
How do they work firing rear? Thinking about doing a 3:1 for my 12s with some plexi work.

Right now i got 36 wide, 13.5 high, and 34 deep. What I want to do is have the subs firing toward eachother with plexi on the sealed side. Do the experts think i have enough room? Would like to tune to 40hz.

Team Ampere
10-30-2012, 08:46 AM
If you graphed them at 1 cf each sealed, figure out what the rsonant freq of the sealed side would be and then tune the portedc chamber to that. It will normally peak a few hz lower than what its tuned at. 2 sealed and 6 ported would be 3:1. theres alot more to it than just this though

fivepoints
10-30-2012, 11:02 PM
if you are any good at math you could pic up this book and figure out the formulas on fourth oders i got the book and it would take to long for me to type up the info and yess there is a lot mor then a 3:1 ratio i am thinking 40hz may still be a tad low depending on the subs most are tuned 50-80 hz for spl comps for sound quality they tune them around 40-60 if you did not have a hatch back throw the sub in a sealed box and cut some tube the length suggested by this book and put them in the rear deck ware the speaker go turns the trunk in to a band pass box but they got to be tuned high like 80-90 to do so casue of the area of the trunk is closer to a .75 to a 4 ratio with new trunks they got now. any ways back on subject if talking how close you can get them to face rear that's tricky. you got to design the box on paper then do the measurements then compare and see if the port is to close to the rear hood. if it is it will never play right if not to close like 8 inch from for a 4 inch port etc. also are you sure you want that weight on those shock's in the back a buddy of mines car bottoms out with a single 12 in it in a wrx hatch wagon.

Loudspeaker Design Cookbook 6th Edition | 9781882580330 | 1882580338 (http://www.valorebooks.com/textbooks/loudspeaker-design-cookbook-6th-edition/9781882580330?utm_medium=referral&utm_campaign=Froogle&utm_source=Froogle&date=10/30/12&buy=3&gclid=CLv-tpOfqrMCFdEWMgodTygAKw)

CAT MAN
10-30-2012, 11:35 PM
derek you wll never be loud. just stop now lool......... or sub up aero back **** slots and octos

Kangaroux
10-30-2012, 11:43 PM
If you graphed them at 1 cf each sealed, figure out what the rsonant freq of the sealed side would be and then tune the portedc chamber to that. It will normally peak a few hz lower than what its tuned at. 2 sealed and 6 ported would be 3:1. theres alot more to it than just this though

4th's dont always peak below their freq. Cabin gain has a lot to do with it and frankly they are pretty unpredictable. My 4th was tuned to 38 and peaked in the mid-high 20's (2:1)

Team Ampere
10-31-2012, 07:59 AM
4th's dont always peak below their freq. Cabin gain has a lot to do with it and frankly they are pretty unpredictable. My 4th was tuned to 38 and peaked in the mid-high 20's (2:1)


If you graphed them at 1 cf each sealed, figure out what the rsonant freq of the sealed side would be and then tune the portedc chamber to that. It will normally peak a few hz lower than what its tuned at. 2 sealed and 6 ported would be 3:1. theres alot more to it than just this though

I know roux, that why i said therers a lot more to it than this.

But damm, tuned at 38 and peaking in the 20s!!!! holy low tuning batman!!

Kangaroux
10-31-2012, 08:13 AM
If you graphed them at 1 cf each sealed, figure out what the rsonant freq of the sealed side would be and then tune the portedc chamber to that. It will normally peak a few hz lower than what its tuned at. 2 sealed and 6 ported would be 3:1. theres alot more to it than just this though

I know roux, that why i said therers a lot more to it than this.

But damm, tuned at 38 and peaking in the 20s!!!! holy low tuning batman!!

I was thinkin of going lower but it sounded good where it was lol

Team Ampere
10-31-2012, 08:18 AM
[QUOTE=nicholasmccabe;8205155]

I was thinkin of going lower but it sounded good where it was lol

lol. Was it beastly on teh lows?? Was there any force behind them?? I cant get any umpph from my lowend

Kangaroux
10-31-2012, 08:27 AM
[QUOTE=Kangaroux;8205161]

lol. Was it beastly on teh lows?? Was there any force behind them?? I cant get any umpph from my lowend

Runnin a single obsidian 12 off my 2200 was movin my whole door panel and shaking around my center console. Would whip around your shirt too if you opened the door all the way and stood there. Honestly it was a wicked nasty setup, sometimes I regret trading it off lol

NoLoud4U
10-31-2012, 08:37 AM
It was just wishfully thinking. I cant fit anywhere near that size. i hate this ******* car

Team Ampere
10-31-2012, 08:37 AM
[QUOTE=nicholasmccabe;8205164]

Runnin a single obsidian 12 off my 2200 was movin my whole door panel and shaking around my center console. Would whip around your shirt too if you opened the door all the way and stood there. Honestly it was a wicked nasty setup, sometimes I regret trading it off lol

Will you pm me sometime today and i will send you some pics of my setup. I need some help on this port. Everythinig i do either sounds like shitt, or decreases output so much i wanna choke this shitt outta something

Team Ampere
10-31-2012, 08:38 AM
It was just wishfully thinking. I cant fit anywhere near that size. i hate this ******* car

I mean , you dont have to go w a huge artio. My 1.5:1 was beastly for what it was. 145 meca style off about 700 watts w/box rise

Kangaroux
10-31-2012, 08:46 AM
[QUOTE=Kangaroux;8205167]

Will you pm me sometime today and i will send you some pics of my setup. I need some help on this port. Everythinig i do either sounds like shitt, or decreases output so much i wanna choke this shitt outta something

Lol sure thing. So your low end is suffering?

EDIT: Just threw your box specs into winisd. It definitely looks like a loud setup but you get heavy rolloff from around 40hz down. If you drop your tuning down to 38-40 that will make a decent difference, but unfortunately you'll also be sacrificing some output. Honestly your box is gonna be pretty **** peaky unless you drop that ported section down to around 5-6 cubes

EDIT #2 (http://www.caraudio.com/forums/usertag.php?do=list&action=hash&hash=2) : White is your current response, teal is the response if you just drop your tuning down to 40hz, and yellow is if you drop it down to 40 and lower your ported volume down to 5 cubes. If you don't mind it being too peaky you may just want to lower your tuning and see how that sounds. How much port area are you using right now?

http://i.imgur.com/8dFX9.png

NoLoud4U
10-31-2012, 09:16 AM
I cant even find 7 cubes gross. Its not going to happen. Im just going to wait and wall it. I dont know if you ever heard the name David Berger but thats who will be doing it. Hes doing Trippi's Hummer right now

Phoenix Risen
10-31-2012, 09:24 AM
you could always pull the back seats and build a full floor...

NoLoud4U
10-31-2012, 09:30 AM
you could always pull the back seats and build a full floor...

Back seats are already out, been out. still not enough room for 7 cubes of box, batts, and the amps.

Phoenix Risen
10-31-2012, 09:37 AM
that *****, i guess i forgot how little that car is. with my back seats gone i have about 14 cubes to work with, depending the height and how im trying to make it load...

Team Ampere
10-31-2012, 09:39 AM
[QUOTE=nicholasmccabe;8205174]

Lol sure thing. So your low end is suffering?

EDIT: Just threw your box specs into winisd. It definitely looks like a loud setup but you get heavy rolloff from around 40hz down. If you drop your tuning down to 38-40 that will make a decent difference, but unfortunately you'll also be sacrificing some output. Honestly your box is gonna be pretty **** peaky unless you drop that ported section down to around 5-6 cubes

EDIT #2 (http://www.caraudio.com/forums/usertag.php?do=list&action=hash&hash=2) : White is your current response, teal is the response if you just drop your tuning down to 40hz, and yellow is if you drop it down to 40 and lower your ported volume down to 5 cubes. If you don't mind it being too peaky you may just want to lower your tuning and see how that sounds. How much port area are you using right now?

http://i.imgur.com/8dFX9.png

roux,

The loading wall has a 16.5tall x 8.5 wide hole in the center. Plan was to have a slide in port. So basically right now there is just a hole. No port walla, just a hole.

NoLoud4U
10-31-2012, 09:45 AM
that *****, i guess i forgot how little that car is. with my back seats gone i have about 14 cubes to work with, depending the height and how im trying to make it load...

Its the height that kill me. Width isnt to great with the rear shocks sticking out into the hatch

Phoenix Risen
10-31-2012, 09:52 AM
yea, i can only go 36 wide with all the panels in, i need to pull them all and remeasure though, i can do 13.5 tall if im going all the way back, or 16 tall if im stopping at the bottom of the glass.

a walled tc would be nasty...

NoLoud4U
10-31-2012, 09:55 AM
yea, i can only go 36 wide with all the panels in, i need to pull them all and remeasure though, i can do 13.5 tall if im going all the way back, or 16 tall if im stopping at the bottom of the glass.

a walled tc would be nasty...

I figured haveing it walled by one of the best and reconing the XLs to 18s would end up being the cheapest route

Kangaroux
10-31-2012, 12:54 PM
[QUOTE=Kangaroux;8205181]

roux,

The loading wall has a 16.5tall x 8.5 wide hole in the center. Plan was to have a slide in port. So basically right now there is just a hole. No port walla, just a hole.

Alright, that would work well for like an SPL setup, though I would try going down to around 100 in^2 and see how that sounds for a lower tuned daily. Have a slide in for your 48hz and then one for the 40hz

Team Ampere
10-31-2012, 01:32 PM
[QUOTE=nicholasmccabe;8205201]

Alright, that would work well for like an SPL setup, though I would try going down to around 100 in^2 and see how that sounds for a lower tuned daily. Have a slide in for your 48hz and then one for the 40hz

SOunds good. I will build something tuned to 40 and shrink port area some. Lets see where that takes us;)thanks man

CAT MAN
10-31-2012, 03:56 PM
It was just wishfully thinking. I cant fit anywhere near that size. i hate this ******* car

i dont think its the car bro. You just dont realize what potential it has because you cant do sh1t til its payed off. If i were you id look into some DD 35 10s and do 4 of those. DD is much more efficient than Dc when it comes down to it.

fivepoints
10-31-2012, 07:39 PM
if you got win isd try looking at all the boxes you are able to find for that sub like ported versus sealed verus bandpass and t-lines etc.... reson is some subs do not preform well in let say a sealed box. ware a ported is better on them. if it preform's well in a sealed i would shoot for a band pass if port preformed well i would go bass horn ot t-line to get more spl out of the sub. if that's is what your shooting for "spl". but still got to use your "ts" specs to help nail it down if this is the best box for it. cause like t-lline there best with a qts of low .2's to high .6's some sub's it helps to model them like the one you have in win isd. some times big ported boxes have better sq then that of a t line.

jdmferio13
11-02-2012, 12:47 AM
I figured haveing it walled by one of the best and reconing the XLs to 18s would end up being the cheapest route

shoot me a pm with dimensions buddy of mine is really good with 4th orders and you dont need 3:1 do 2:1 U have the room just have to figure out how.