you should use a height to width ratio less than 1:8?

[perfecxionX 10+ year member]

in planning a box for an 18"q, the carstereo.com port length calculator is telling me

"you should use a height to width ratio less than 1:8"

is this important? i want the sub and port firing up, and if possible i want the port running the long way --- this is what i have so far (length using winsid)

http://s126.photobucket.com/albums/p116/perfecxionx/?action=view&current=6.jpg

also, i just noticed that carstereo calc not only gives me a 5 inch difference in length (compared to winsid), but it changes the estimation if i switch the height and width values(same #s, different place)?

Click to read more...

 

[Volenti 10+ year member]

A long thin port will resonate differently compared to a square or round port of the same area, that's the reason for the ratio suggestion.

Positioning the port on the short side of the box is the better option since the port ratio will be lower.

 

[perfecxionX 10+ year member]

i see, why does it change its prediction when the values for height and width are switched?

(http://www.carstereo.com/help/Articles.cfm?id=31)

 

[Volenti 10+ year member]

i see, why does it change its prediction when the values for height and width are switched?

(http://www.carstereo.com/help/Articles.cfm?id=31)

I don't know, bug in the program?

Use the length calculated by winisd.