i have 2 alpine type-r 12' subs in sealed enclosures. the make a hell of a punch, but im thinkin the sound quality is great but i want more more more, so is it possible to just throw sum ports in my (1ft air space each) sealed boxes?? the air space is exact, alowence for sub n all has been made.

=just wunderin=

It is unlikely that you will get much of a decent tune by just "adding a port" in a small enclosure as it is bound to tune quite high/need a very small port area that will make a fair chunk of port noise.

The sheer volume of port you would need would make the nett enclosure tiny.

Porting properly requires a "total system" approach requiring a larger total enclosure to achieve a good tuning. Coming from a sealed design, you would need to tune fairly low meaning likely a box of 2.5 to 3 times the current size for a Type R.
I have done a few of these now.....

12" Alpine Type Rs can sound very good in 1.5 cu/ft net per sub, tuned fairly low. However, the problem with small ported enclosures is the large port lengths required as well as the fact that there is less space to fit the port. A smaller enclosure will also generally put out less bass down low, but this is relative to the subwoofer specifications. If the box is too large, then it may put out too much bass down low and be a bit of a one note wonder.

[ January 06, 2003, 02:56: Message edited by: 1337shiznit ]