tuning frequency help...

[platnum accord 0]

ok so between my 2 15's im going to have about 400 square inches of port area, and i need to know if figuring out tuning frequency is the same as like a round or slot port.

or if 400 is too much lemme know.

i have figured 355 per sub so 2/3rds of that is about 220 per sub.

but the box is going to be aboue 3.5-3.8 cubes per sub and i would like it to be tuned to around 35 hz. but i have no idea how long i need to make the port or anything like that.

so any tips or tricks are well appreciated.

Edited June 23, 2007 by platnum accord

[mrray13 30]

wow, with that much port area, and that little of a net box, that's going to be one massively long port.

so, just to clarify....

7-7.6 cubes net for the box

400in^2 of port

35hz tuning

for example, a port 10" x 40" will need to be ~80" long to achieve that tuning, in that box, with that kind of port area

wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

[helotaxi 46]

i have figured 355 per sub so 2/3rds of that is about 220 per sub.

Where'd you get those numbers? Is the 355 supposed to be the cone area of the sub? If so, you're not even close. A typical 15 is gong to have a cone area around 110-115 in^2. 100 in^2 should be plenty and give you a managable, though still pretty long, port.

[platnum accord 0]

ok lol proof once again i know nothing when it comes to boxes...

did you use pi r^2 because thats what i used and about a 6 inch radius.

Edited June 23, 2007 by platnum accord

[platnum accord 0]

oh so i took some measurements and the max depth from the front of the box to the rear is around 35 inches

so maybe i should just build a sealed box hahaha.

Edited June 23, 2007 by platnum accord

[helotaxi 46]

ok lol proof once again i know nothing when it comes to boxes...

did you use pi r^2 because thats what i used and about a 6 inch radius.

pi* r^2 would give you 108 in^2 where'd you get 350.

[Adrian_D 520]

and why 400sq in of port area ?

[platnum accord 0]

my mistake on the cone area. i was doing pi * r then squaring the whole thing...

lol yeah... im not to bright.

ok but again i want the subs to just eat up all the lows. ive figured it out. the max port length i can have is about 29, and with a width of 5-1/4, and a height of 15, the lowest tuning i can manage with one long straight flared port is about 30.

on 2 15's would i want to tune it to 30? or would i want to go lower or higher?

[turtles1118 1]

ok so between my 2 15's im going to have about 400 square inches of port area, and i need to know if figuring out tuning frequency is the same as like a round or slot port.

or if 400 is too much lemme know.

i have figured 355 per sub so 2/3rds of that is about 220 per sub.

but the box is going to be aboue 3.5-3.8 cubes per sub and i would like it to be tuned to around 35 hz. but i have no idea how long i need to make the port or anything like that.

so any tips or tricks are well appreciated.

Well hearse what i came up with,

Box Width-40"

Box Height-27"

Box Depth-27"

Box Volume (ft3) 7.40

Tuned Frequency of-34.57

Square Port Area of-161"

Wood Thickness-2"

IMO that would be abut what your looking for right? Hope this helps.

Edited June 29, 2007 by turtles1118

[mrray13 30]

my mistake on the cone area. i was doing pi * r then squaring the whole thing...

lol yeah... im not to bright.

ok but again i want the subs to just eat up all the lows. ive figured it out. the max port length i can have is about 29, and with a width of 5-1/4, and a height of 15, the lowest tuning i can manage with one long straight flared port is about 30.

on 2 15's would i want to tune it to 30? or would i want to go lower or higher?

30hz is plenty low. i wouldn't tune any lower then that.

wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

[platnum accord 0]

well the box is very oddly shaped. i did it in a way so that it kinda forms around the curves in the trunk.

i worked out all the internal dimensions to get 7 cubic feet before port displacement.

i want to know what will give me the better range of bass. i know 34-36 is where i will have a nicer curve. but i was wondering with 30Hz tunage will i get alot of rolloff?

[ANeonRider 3]

Rolloff? It is there in bunches on the low end no matter what you do because you are porting.

I do recommend not using audio terms if you don't know the meaning of them completely though

In my world, I'd tune to 30Hz. Low end good for music, since that is what I like listening to.

[platnum accord 0]

i know what i ment, and you most likely do too lol.

like the slope a crossover has or the slope a subsonic filter creates lol.

i dont know all the terms and im trying lol.

just a question, what is the right term? like i did end up tuning it to about 30 hz, i think it might be about 29 in the end, but am i going to be missing out alot on the high tones? like 50-60 hz?