Re: 4th order design 2 alpine type r 15's
there is so many variables really. A 1:1 ratio normally work well unless the woofer in question doesnt like seal boxes then I tend to go on the large side for the sealed like 1:1.15
But then you have subs that like sealed boxes. Then you can go larger with the ported side to gain efficiency.
Personally I never go past 2:1 ratios as the pass band is just way too narrow and I never push enough power to need that kind of box.
1/2 to 1/3cone area for port area tends to work well leaning towards the larger port.
passive radiators are not advised for this kind of box they will almost always be damaged.
last few boxes I built were tuned between 46-48hz tuning lower takes alot off the high end and pits it on the bottom end and vise versa
2012 Nissan Versa Hatch
in need of everything cept deadener ive got that done