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87guy
10-06-2005, 01:51 AM
woo first post ever! anyway... i've got a 94 sierra extended cab and i'm itching to make it boom. i'm thinking 3/4" mdf sides slobbered in resin... glassed in bottom and either 1" plexi on top or just 3/4" mdf resin'd and braced appropriately. i want to run an adire audio brahma 10" with 900wrms to it tuned low... maybe 30hz... ok. i know the port needs to be on the same side of the box as the sub... the only way i can make this setup work is with an upfiring box... i'm probably going to have to modify the bottom of the seat in order to deal with excursion... woo fun. anyway my question is about upward firing boxes... i've read other posts but it's got hardly anything to do with them... it's all downward firing or forward... i know the characteristics of downward and forward firing boxes. i'm wary of upward firing boxes because the woofers might load weird... any help would be appreciated...

95stroked1500
10-06-2005, 02:19 AM
fire the sub up is fine, no loading issues. has better sq than down. put the sub on the passenger side, port firing forward on the driverside, or out the side of the box on the driverside facing the driverside wall. it'll work as good as the rest of them.

87guy
10-06-2005, 02:52 AM
ah thanks a bunch. i was worried it'd be retarted. i know using resin on the walls of the box raise the tuning frequency a little bit so do you think i should compensate by lowering the tuning frequency? or just say it is what it is? also it was my understanding that in cars and suv's the port should be on the same side as the sub... unlike say... a crx with the subs up and ports back... heard you can get weird cancellation issues... unlike in a transmission line box, where the sound is directed out the port, the port in a regular vented box increases pressure and increases sound coming from the woofer itself... not the actual port(+3db, yay).(lazy explanations that i'm not sure if you know or not) anyone have any knowledge of snail shell enclosures? i've always wondered about them... and thanks hah

95stroked1500
10-06-2005, 09:28 AM
"i know using resin on the walls of the box raise the tuning frequency a little bit so do you think i should compensate by lowering the tuning frequency? or just say it is what it is?"

tune where you have planned and call it good.

"also it was my understanding that in cars and suv's the port should be on the same side as the sub... "

nope, not always true. you can put it on the same side as your sub. should work fine for what you're doing either way.

87guy
10-07-2005, 01:22 AM
sounds good i was planning on doing the sub on the drivers side because of the mounting depth the sub will barely fit. with the handle on the pass side the sub might not fit... plus there needs to be room for excursion... might have to end up modifying the underside of the seat... anything wrong with firing the port upwards? i don't really want anything off of peoples shoes deciding to float around in my box.

95stroked1500
10-07-2005, 02:26 AM
it's easy enough to make a relief for the handle. i've done it. up with the port is not good. you do not want your port to be hindered in it's ability to flow freely. aka....no

obstructions or restrictions in front of it. you want at least a port diameter space between the port and anything in front of it. fire it out the side of the box. don't

worry that it isn't on the same side as the sub. it will work just fine. this spring, i am going to rebuild the gf's box, with the subs forward and port out the side. she has a

sealed prefab right now (probox, good box). counter sink your sub in the box, and maybe make a ring to go around your sub that sticks up to keep the seat material off

of it. or just put a grill over it. there's decent grills these days that aren't gay like the old "waffle" type.

87guy
10-07-2005, 03:07 AM
ah okay i'll port to the front seeing as i need all the volume i can get. the relief for the handle will definately be done, but the sub has to be positioned just right... between the stupid hump and the mounting depth, the sub will barely fit... and i suppose it wont get that dirty... it's rwd so no 4x4ing. i'm going to have to put a grille on so the sub wont rub/hit the seat. thanks for the help though, i would've screwed it up and put the port on top following that other rule of thumb... beh. if you want i'll let you know how it turns out once it's done :rocking:

by the way... starting the glassing this weekend.

95stroked1500
10-07-2005, 09:47 PM
i think we all would like to see some pics and hear the story.

don't rule out putting your port to the side.

cajundragger
10-07-2005, 09:58 PM
My sub forwards fires on the drivers side and port forward fires on the passenger side....I love it...great sq and can't tell where the sub actually is unlike most setups I listen to...

87guy
10-07-2005, 10:46 PM
i just thought of something... to make sure there's no confusion... you mean port the box towards the side of the box.. or the side of the front of the box?

95stroked1500
10-07-2005, 10:56 PM
pm x6369x and ask for a pic of the box he had his 8" kickers in. the port in particular. he ran it out the side. like if you're sitting in the back seat, the port is on the left, firing left, towards the side of the vehicle.

or else i can draw a quick picture of what i mean and post it if you like.

87guy
10-08-2005, 01:01 PM
sounds good, i'm just not sure how i'd do that without leaving a 4" gap on one side of the box.. not very cosmetically appealling. i guess i could always tuck my jack in there and put the tire iron behind the box...

87guy
10-08-2005, 01:07 PM
i took a look at x6369x's website and it's got pics posted of the install you were talking about... looks like the guy hits some pretty high #'s. i suppose i could always do it that way

87guy
10-08-2005, 01:10 PM
i'm also planning on wiring a second battery and doing 4 gauge runs from alt to batt... ground to body... and eng block to body woo