I have a 12" Apline type R sub, I've been reading various DIY ported box formulas, including those on Loudspeakers101.com. By entering my Subs parameters I get Vb=1.912 ft^3, Fb=27.1 Hz
I get a minimum port diameter of 5"? does this seem too large? If I use this value of port diameter then the length has to be 34"??? how do you fit that into a box of only 1.91 ft^3?
I know if I go with a 4" port then the required port length begins to drop, but wont i get too much air noise? should I use a higher Fb then the one that was calculated? say 30 HZ??
Any help to clear this up for would be greatly appreciated, thanks.