square port

[jizazz12]

porting the rear deck of my Impala, subs will be firing into the cabbin . Subs are two 15" xl m1's on a Crescendo 3kwp. My question is since the port won't be connected to any walls of the box can i still use the calc to figure out the port area? In other words what i'm asking is when your doing a standard slot port your normally using the side wall or the top and bottom of the box as part of your port, what i'm wanting to do is come thru the top center of the box with a partially external port thru my rear deck and i wasn't sure how to figure this out with the calc. I currently have two LVL4 15's firing into the cabin with 4 4" aeros in the rear deck but i'm thinking i could get a little more port with a square/slot port than the aeros due to the flares. Any help with this would be greatly apprciated, and if the square/slot port isn't going to get much more than what i have now than i'll just stick with what i know.

[Kranny]

if the port isnt touching ANY sides, then its 0 for # of common port walls.

however much the port sticks out of the box, is the number you put in for external port length

[Chris Hammer]

Wont the port take up the same amount of airspace regardless? Hmmm maybe it will be off one side by 3/4 so you might have to accomodate that but Im not sure..Im tuned in for an answer.

[Kranny]

if a 20" port is sticking out of the box 10", then it will only take up 10" worth for displacement. get what im saying?

[jizazz12]

Thank's for chiming in Kranny, so i could just plug my numbers into the calc and hit 0 for common port walls and should be good as far as ware i place the port on the top of the box? and in your opinion what do you suggest tuning these to i was thinking 33HZ it's a daily ?

[Ddub847]

U need less port with aero ports

[412 CVX]

I think it's gonna be hard to tune that low with proper port area if you're porting through the deck. but yeah 33-35 should be good

[ChevyBoy95]

Wont the port take up the same amount of airspace regardless? Hmmm maybe it will be off one side by 3/4 so you might have to accomodate that but Im not sure..Im tuned in for an answer.

no, because the thickness of mdf will be different, rather than sharing a wall of the box.

[jizazz12]

The lvl 4's sound great and get low with the aeros, the box i have in there now is tuned to 32.5 but i could only get 4 of the aeros in the deck because of the flares i wanted to do 5 but they just wouldn't fit. I figure i would look into the slot port and see if i could get more port area this way figure it would be worth looking into.

[ChevyBoy95]

Thank's for chiming in Kranny, so i could just plug my numbers into the calc and hit 0 for common port walls and should be good as far as ware i place the port on the top of the box? and in your opinion what do you suggest tuning these to i was thinking 33HZ it's a daily ?

33 should be perfect, im running 2 m1 xls on about the same power, 6.5 cubes with 2 6in aeros tuned to 31hz, plays down to about 25hz with authority, but i do loose some upper bass notes.