possible box designs??? 1st. timer

[jfink 10+ year member]

This is my first time building a box but i do have some wood working experiance. I have a 10" alpine type-r and was looking to make a box according to alpine's specs. Got on their website and got their box dimsension and info and are as follows, this is for their optimum vented box if you check out their website.

External box dimension: 12.5"x14.5"x17.25"

Gross internal volume: 1.3ft.cu.

Vent area: 11in.sq.(11"x1")

Vent length: 22in

Vent Displacement: .237ft.cu.

Net internal volume 1ft.sq.

at 30hz??

Not forsure if it 12.5 wide x 14.5 tall x 17.25 deep

or all the other combinations of the 3. Or the design of the port since no side is long enough for 22 inches of port.

I'm figuring one solution is to have the box 14.5" wide x 12.5" tall x 17.5" deep.

Have the port along the right side of the sub going from top to bottom extend 15" to the back which would leave 1" until reaching the back and then 90 degree turn for another 7". I can make designs of MS paint if it would help, just gonna take a minute. This is also using 3/4" MDF.

Click to read more...

 

[jfink 10+ year member]

so can someone at least tell me that when alpine says to have the port length be 22in. is that 22in. in one continous stretch or can it be 22in. all together(with bends)? ANY help would be appreciated.

 

[skmfkr 5,000+ posts]

total

 

[jfink 10+ year member]

thanks for your help. I owe you a beer.

 

[skmfkr 5,000+ posts]

ive already got one, you need to measure down the center of the port also not the walls, well only if it turns

 

[GearGuy2001 10+ year member]

Thats kinda of a small port for every cube of box space you want 13-16 square inches of port (thats a bit high but ok) so what about 1.25"

Also I think they gave the internal dimensions? Because once you take out .75 for wood (off the "external" dimensions) you box is around .9 cubes

Check out this website http://www.reaudio.com/speaker_box/LPort_Box_Calc.html

Put these numbers in:

Box Width-18

Box Height-13.25

Box Depth (T&B)-15.25

Port Width-1.25

Port Length 2-9

That box above is 1.3 Cubes @ 32.6Hz

 

[jfink 10+ year member]

skmfkr Re: possible box designs??? 1st. timer
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ive already got one, you need to measure down the center of the port also not the walls, well only if it turns

did not know that, thanks. gonna have to sit down and draw up some plans and scan them in to see what you guys think. really want this box to turn out good.

 

[jfink 10+ year member]

Also I think they gave the internal dimensions? Because once you take out .75 for wood (off the "external" dimensions) you box is around .9 cubes

first off that website is pretty cool, even tells you how to cut each peice.

But onto the task at hand, the only reason i am going off their specs is because i have no idea how to design a box, i can build it, just not design it. Don't wanna pay somebody money to design one when i can get it figured out......eventually.

also the frequancy response for the sub is 24hz-600hz so i'd like to keep the ports tuning as low as possible.(may understanding being that the port's tuning frequancy determines how low the subs frequancy can go until it blows)

 

[skmfkr 5,000+ posts]

lol your not gonna blow a sub from playing below tuning. i wouldnt both tuning below 32hz, i usually dont tune under 35hz

check out the top 3 links

http://www.google.com/search?hl=en&q=port+size+calc&btnG=Google+Search&aq=f&oq=

 

[jfink 10+ year member]

thats a lot of information right there. Definatly going to draw up some designs and see what i can come up with. any body know a good frequancy for the port off of a alpine type-r 10" dual voice coil.