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GCAdidas13
05-18-2005, 09:15 AM
When firing forward, I have heard that you must seal off the rest of the trunk from the baffle.

I was thinking about doing this with fiberglass.

Picture this: The baffle of my box is 39" wide and about 18" tall. It sits about 12" in from the front of the trunk, and the back seats are down. The opening behind the back seats is 13" tall and 35" wide. In order to use fiberglass to seal this off, I would glass from the edges of the baffle to the edges of the opening. Basically this will become a reverse-horn.

Will this do anything weird with how my subs sound? I figure that it could affect tuning, limit air flow, or turn my box into some sort of bandpass box because the opening is smaller than the baffle itself.

If you need a visual of how it looks, I'll paint something up for y'all.

Thanks

swimfreak26
05-18-2005, 09:33 AM
From what I understand, that would basically be a wall....you can fire into your cabin without sealing it off, it's just generally not as loud as firing towards the trunk (and in your car i can guarantee it's not as loud).

A wall would be fun to try, but it's quite a bit of work to get it right.

GCAdidas13
05-18-2005, 09:40 AM
Well I understand that it's going to be a wall... it's just that after the wall, to seal the box from the rest of the trunk I was going to do this:

http://img269.echo.cx/img269/6048/dscf22335bi.jpg

That is a side veiw of the box... All the brown is MDF and the sub is the black... The port also is directed to the left.

I was wondering if having something like that would affect tuning or capabilities of the subs.


Thanks

swimfreak26
05-18-2005, 09:59 AM
I'm not quite sure...I would guess you'll get some cancellation there, but that's totally a guess. Talk to jmac or lloyd, they both have experience with walls.

req
05-18-2005, 10:00 AM
looks good on paper.

GCAdidas13
05-18-2005, 12:07 PM
bump. someone that has any idea tell me :D

req
05-18-2005, 12:16 PM
talk to karleon. he did this exact same thing. but he used two deathpenalty 15's - but his were mounted - more or less - flush with the back seats.

GCAdidas13
05-18-2005, 12:17 PM
:rolleyes: im not concerned with the wall i just want to know if the reverse horn will decrease or affect output

GCAdidas13
05-18-2005, 04:44 PM
jmac be here for me

noob with an RS
05-18-2005, 04:58 PM
i summon JMAC to this thread! :thunder strikes and jmac appears:

Shyne151
05-18-2005, 05:36 PM
...

http://www.project04.net/gallery/main.php/view/MonteCarlo/system/current/IMG_2548.jpg

http://www.project04.net/gallery/main.php/view/MonteCarlo/system/current/IMG_2549.jpg

lotas
05-18-2005, 06:26 PM
I dont get 100% what you mean but you will get cancellation if you face your subs forward, but they will be louder when you have your trunk open.

here:

http://www.caraudiocentral.net/forums/showthread.php?t=233

Shyne151
05-18-2005, 06:55 PM
I dont get 100% what you mean but you will get cancellation if you face your subs forward, but they will be louder when you have your trunk open.

here:

http://www.caraudiocentral.net/forums/showthread.php?t=233

Wrong.

If you properly seal off your cabin from trunk they won't. Like in my car :)

GCAdidas13
05-18-2005, 10:24 PM
ok i will try to explain one more time.

the baffle of the box is 39" by 18" and cannot be smaller.

the opening of the trunk is 35" by 13" and cannot change.

if I glass from edge to edge, the sound coming from the subwoofers will have to go through a cross sectional area that smaller than the baffle itself, through the opening.

i am concerned with this being a problem in any way, shape, or form.

get it?

GCAdidas13
05-19-2005, 01:08 AM
yeah?

GCAdidas13
05-19-2005, 09:00 AM
bump

GCAdidas13
05-19-2005, 09:05 AM
alright my buddy OurManFlint (THANATOPSIS from Sounddomain boards)

told me that I'd be fine. The Sd of the Avalanche is 749 square centimeters, which is 116 square inches, which means that's 232 square inches for both, and I plan to include 105 square inches of port, so that's a total of 337 square inches.

Seeing as the hole going from cabin to trunk is 35 by 13, that's 455 square inches, which is definitely more than the area of the subs and port together. so i'll be fine. :D

ngsm13
05-19-2005, 10:32 AM
I coulda told ya that dummy... ;)

What do you thing most blo-thru's in truck do??!?! lol...

NG

GCAdidas13
05-19-2005, 11:10 AM
There you go. Where were you two days ago!?