Designing a ported box with George

[jellyfish420 10+ year member]

Bbp6

 

[jellyfish420 10+ year member]

im lost now

whats up???

 

[jellyfish420 10+ year member]

im lost now

whats up??? where you lost

 

[Thuracine187 10+ year member]

just dont see how i cant get those numbers for the length. im pretty sure im doing the formula correct

 

[jellyfish420 10+ year member]

just dont see how i cant get those numbers for the length. im pretty sure im doing the formula correct

well when you do the formula what number are you using for you port area?

you said 5" diameter but thats not area...is that what your using?

 

[DBfan187 5,000+ posts]

Bbp6

I don't know what I would do without it...eh, I'd probally bug the shit out of Jmac.//content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[jellyfish420 10+ year member]

I don't know what I would do without it...eh, I'd probally bug the shit out of Jmac.//content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

don't get me wrong i can do it on paper...but i'm already sitting at the computer. its just easier to push a few buttons//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[DBfan187 5,000+ posts]

don't get me wrong i can do it on paper...but i'm already sitting at the computer. its just easier to push a few buttons//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Oh, I can too. But you'll just have to get back at me in about a month.

 

[Thuracine187 10+ year member]

im using 82.5 16.5*5 maybe i should go get some paper cause im using my ti-83

 

[jellyfish420 10+ year member]

come up with like 60-70 inches?

 

[Thuracine187 10+ year member]

like 81

 

[jellyfish420 10+ year member]

he man you got aim? it'll be easier to talk on there?

 

[Thuracine187 10+ year member]

ygpm

 

[LightningStryk7 10+ year member]

bump for someone

 

[IshbOO 10+ year member]

im trying to design a box now with this method and I'm having trouble finding out my second wall length. I get a negative number everytime I try to do so.

outside 16x33.5x20

inside = 14.5x32x18.5

Port

14.5x3

Fb is the tuning frequency you want: 34hz

Vb is the internal volume of your box: 4.0cuft

Av is your port area (height x width of the port face): 14.5*3 = 43.5

Lv is port length: 18.41

18.41 - 1.5 = physical LV(portlength) 16.91

step 6 + 7

16.91 - (10in + 1.5mdf) = 8.41

(8.41 * 3 .75 )(14.5*) / 1728 = 0.26^3 displacement

First wall 15*3.75(14.5)/1728 = 0.44^3 displacement

.18+.18+.2199+.44 = 5.0199^3 box size, after displacement

depth 18.5

wall one 18.5 - 3 = 15.5

wall two 16.91 - ( 18.5 +1.5) = -3.09

 

any help? plz thanks

 

does this mean i dont even need that second wall? or what im confused?