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IMOVeCHICKENS!
12-02-2009, 05:32 PM
420 sq in of port good for 1 hdc3 10 tuned to 39.5 hz in 1.5 cubic ft?


just want to know if i did my math right and this all makes sense lol

SPLluminator
12-02-2009, 05:40 PM
420 sq in of port good for 1 hdc3 10 tuned to 39.5 hz in 1.5 cubic ft?


just want to know if i did my math right and this all makes sense lol

I think you messed up somewhere lol. Are you talking about port area? Because you should only need about 24" of port area. And the port length should be about 23" for a slot port, and 24" for an L port.

PV Audio
12-02-2009, 05:42 PM
Umm...do you mean 024 instead of 420? Do you realize how much port area 420 square inches is.

IMOVeCHICKENS!
12-02-2009, 05:44 PM
well yea i guess i ****ed up some how here are the dimensions of the port

2 wide
10.5 height
20 length

sound about right for 1.5 cubic feet?

bass-aholic
12-02-2009, 05:45 PM
how the hell did you get that?

IMOVeCHICKENS!
12-02-2009, 05:46 PM
very poor math skills and probably smoking way too much

SPLluminator
12-02-2009, 05:48 PM
well yea i guess i ****ed up some how here are the dimensions of the port

2 wide
10.5 height
20 length

sound about right for 1.5 cubic feet?

Yes that is correct! When you do port area you do the Height X Width. Port length isnt calculated into this number.

Just an FYI: The port you said would be like 42" tall by 10" wide for example. Lol. Itd be a lil big for that 10 haha

IMOVeCHICKENS!
12-02-2009, 06:00 PM
cool cool thanks man i rally wanted to use a 8 inch flared aero but it says id need 50+ inches length of port to achieve a 40 hz tuning lol

PV Audio
12-02-2009, 06:03 PM
Why the hell do you need an 8" aero for a 10" speaker?

SPLluminator
12-02-2009, 06:05 PM
Yea you would only need a 4" at most

IMOVeCHICKENS!
12-02-2009, 06:06 PM
Why the hell do you need an 8" aero for a 10" speaker?

the wow factor but i guess itll have to wait till i get a second 10 from AQ


for the pair 20 in's of 8 inch port for 3 cubes after sub and port displacement gets me like 39-41 hz

SPLluminator
12-02-2009, 06:09 PM
So you want them to say "wow your retarded for using that big of a port" lol.

amartin_72
12-02-2009, 06:09 PM
wow. Yeah square as in square inches means multiplying two sides of something, not three- thats cubes. 2 by 10.5 would be 21 square inches and 420 cubic inches for a 20" long port. To use the 8" aero you would need two big tens, but this type of box makes them LOUD. One 6" works good for a big 10, usually sacrificing some SQ- big ports on small boxes usually dont sound the best.

James Bang
12-02-2009, 06:12 PM
I didn't know you could measure SQ by inches.

amartin_72
12-02-2009, 06:13 PM
This box was built for two HDC3 10's getting 1500RMS each. 2.9 cubes. Its hard to get down in the 38hz range with a huge port and still fit two big subs in there. It helps large sub boxes get loud when they don't need 20" long ports for 38hz tuning, even given the same square inches of port per cube.


http://i37.photobucket.com/albums/e76/amartin_72/3%20cubes%2039hz/hlkkkjkk035.jpg

http://i37.photobucket.com/albums/e76/amartin_72/3%20cubes%2039hz/hlkkkjkk037.jpg

cj407
12-02-2009, 06:14 PM
you only want 16sq in of port per cube...so 24 sq in would be fine...2" wide port 12" tall.or 3" wide 8" tall

cj407
12-02-2009, 06:22 PM
wow late post...oh well point is still across you only need 20-24 sq in of port if doing slot...if doin aero 1 4" port will be enough

IMOVeCHICKENS!
12-02-2009, 06:24 PM
yea i dont know what i was thinking about that port idea but it shouldnt be too tough to build this box i designed built my first sealed box for my 2 15s and i hit a 142 so i got the concept down ^^

jonny101abc
12-02-2009, 06:55 PM
don't smoke weed when doing box designs, your numbers will be off LOL

IMOVeCHICKENS!
12-02-2009, 08:12 PM
hell yea they were off wonder if its a coincidence that i got 420 sq in of port lol

basscort2009
12-02-2009, 08:22 PM
420 sq in of port good for 1 hdc3 10 tuned to 39.5 hz in 1.5 cubic ft?


just want to know if i did my math right and this all makes sense lol

sig'd! lol i think instead of length x width u did length x wide x depth of the port. honest mistake

D.Joymn
12-03-2009, 04:45 AM
I found some plans for a loft bed that would suit our needs very well, but they are metric. I am thinking of just converting all of the measurements to inches, has anyone done this and if so, what types of problems will I see when I finally start cutting and nailing?

Thanks.

Blue Fury
12-03-2009, 05:00 AM
Its a shame people can't even understand BASIC dimensional analysis.

Unit Length x Unit Length x Unit Length = Unit Length^3, NOT Unit Length^2

IMOVeCHICKENS!
12-03-2009, 08:25 AM
sig'd! lol i think instead of length x width u did length x wide x depth of the port. honest mistake

exactly what i did but atleast my measurements where right lol

PV Audio
12-03-2009, 09:27 AM
I found some plans for a loft bed that would suit our needs very well, but they are metric. I am thinking of just converting all of the measurements to inches, has anyone done this and if so, what types of problems will I see when I finally start cutting and nailing?

Thanks.
Um, who exactly is our?

King_corral
12-03-2009, 12:37 PM
This is somebodys sister in my avatar.

basscort2009
12-03-2009, 12:38 PM
exactly what i did but atleast my measurements where right lol

yea they were right though! lol