Can somone check my work? (with pictures)

[DarkFox 10+ year member]

Hey, got a new box I am working on here, it is for one Kicker L7 10" sub. I need this checked to make sure mainly that the porting is right, but also just to make sure I didnt mess up anything else. All the info is in the picture. All this is assuming I used 3/4" material to make the ports. Thanks

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[Ingleside 10+ year member]

i assume the 14" and 30" are internal dimentions?

EDIT: im getting 31 htz

 

[DarkFox 10+ year member]

yeah Ingleside, thats what the bold letters at the top of the pic say anyway... Thanks for checking it though, however when you calculated it, did you use just the volume shown, or did you take into considereration the displacement of the woofer? But thanks again for taking a look at it.. At least I know I am close... Even if it ends up being 31 and not 32 Its not exactly hurting me.

 

[3onDubs 10+ year member]

The 2" on the port opening isn't right.....that should read 2.75"

 

[DarkFox 10+ year member]

no, the 2 inch port opening is right.... I designed it afterall. And jmanpc, what are you trying to say? if its a 2 inch port then is is 1 inch from center to where the port wall starts, then add in the 3/4 inch for the material, then add another inch to get to the center of the port heading in the opposite direction. That looks like 2.75" to me. and thats not a measurment for all those sections, each one is marked in its own location.

EDIT: I think you were looking at the 2.75 at the very top of the picture, that is not the port width, but rather a measurment to be able to calculat the space above the port that counts towards the airspace of the box. If you look close, the marker line on the right is placed at the outside edge of the port, which means 2 inches worth of width for the port + 3/4 inch for the material, giving 2.75" X 4.75" X 14 or a volume of 0.11 cu. Ft. for that area of box to be added to the rest of the box.

EDIT #2: Looked closer at the picture and can see why you thought that was a internal port dimension, I can only do so good with paint. Sorry, but my explination above is what it is intended to be.

 

[ramos 5,000+ posts]

Numbers look right too me. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Ingleside 10+ year member]

yeah Ingleside, thats what the bold letters at the top of the pic say anyway... Thanks for checking it though, however when you calculated it, did you use just the volume shown, or did you take into considereration the displacement of the woofer? But thanks again for taking a look at it.. At least I know I am close... Even if it ends up being 31 and not 32 Its not exactly hurting me.

i took into account the effective port lenght, which in your case is 33 inches.

when i plug in 28 for area, 33 for length and 3611.52 for volume into my spreadsheet it give me 31.07 htz.

close enough though

 

[ramos 5,000+ posts]

I get 31.07hz too. But I doubt he will be able to here any difference. He!! it might give it a tiny bit better low end //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif