Check my math 8.0cf net @ 34hz, 2 6" ports?

[I Like Waffle]

Doesnt seem like i can get enough port volume using 6" ports (60") i can do that or a 5-6" slot port, max height on box is 18"

I drew up a 5.5w x 16.5t x 18 slot port which netted me 135" of port volume which is 17" per cube. Sound good? I thought it was 12-14 per cube was optimum?

Box is for spl, 2 15s on 3kw in a wall. Not concerned about sq.

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[RAM_Designs 5,000+ posts]

What are you tuning to? Is this going to be a burp box?

 

[MONSONwarrior Premium Member]

What are you tuning to? Is this going to be a burp box?

34 hz.. in title.

 

[RAM_Designs 5,000+ posts]

Haha, didn't catch that.

 

[RAM_Designs 5,000+ posts]

16.5" x 5.5" = 90.75in^2 of port

90.75in^2 / 8ft^3 = 11.34in^2 per ft^3

 

[I Like Waffle]

16.5" x 5.5" = 90.75in^2 of port
90.75in^2 / 8ft^3 = 11.34in^2 per ft^3

Your numbers sound a little off to me. I changed my design though, decided to go with 6 x 15 x 18. Looks like exactly 135" of area to me.

IIRC you also take into account the length correct? I do length times width times height divided by 12 to get sq in, or divided by 1728 for sq ft.

 

[rosshimself13 10+ year member]

Your numbers sound a little off to me. I changed my design though, decided to go with 6 x 15 x 18. Looks like exactly 135" of area to me.
IIRC you also take into account the length correct? I do length times width times height divided by 12 to get sq in, or divided by 1728 for sq ft.

no you need to slow your roll a bit

port area is width times height

pors displacement is lengthx heightx width/1728 but you also need to add the thickness of the wood in your case it would be a central port so lengthx width+.75x height+.75/1728 assuming you use 3/4 inch mdf

 

[I Like Waffle]

ok, well if thats the case it leaves me with 99 sq in of port, which is still enough for the box apparently. All this time ive been building my own boxes thinking i have 18" of port per cube when i only have 12-14. I guess i read wrong somewhere.