View Full Version : box for alpine type r

07-31-2003, 01:54 AM
ok guys, here's the deal.

im looking to build a ported box for my 12 inch type r. i seem to have missed something when i've read about ported boxes because i have no shittin idea about how to tune a box to so many hz. i dont have any idea on port length or anything like that. what i need to know are some good measurements on building a nice ported box that would give a good mix of sq and spl.

also, if someone could explain how to tune a ported box, that would be greatly appreciated.

im sure that this has been discussed in other threads, but i've never seen how to tune a box on here, so please, dont give me any **** for not reading up on it before i posted.

thank you

07-31-2003, 01:36 PM
Find the suggested airspace (cubic ft) then find the suggested Fs (Hz), then post some measurements that you can work with and the frequency you want it tuned to. Then I can figure it out for you :) You tune a box by the Height, Width, Depth of a port.

07-31-2003, 08:35 PM
the suggested volume for a ported enclosure is .75-1.75 cu/ft.

the fs is 27 hz.

im really flexible on the dimensions. the box is going to go in the back of my 1964 cadillac, and the trunk is huge. there's been times when me and a friend have just backed it up somewhere and put our lawn chairs up in the trunk and sat right there. so size really isnt an issue.

thanks for the help

07-31-2003, 08:47 PM
ok that sounds good, thanks a lot

now you mean 4" in diameter right?

and if you mean a 4" tube, does the location of it in the box matter?

sorry for all the ?'s, i really do know some **** about car audio, just never had any idea about ported boxes.

07-31-2003, 08:51 PM
You can go 16" wide and 16" deep w/ a height of 14" and thats about 1.52091 cubes(internal volume, if you use 3/4"), or you could go 14" wide 14" tall, and 15" deep and you get about 1.2207

07-31-2003, 08:54 PM
if i do either of those two last measurements i wont be able to fit a 22" port in there, unless you had a different idea on the port?

07-31-2003, 08:59 PM
well what im saying is a 22" tube wouldnt fit in one of those boxes that was mentioned, unless im really missing something here

07-31-2003, 09:07 PM
alright i smell what your cooking now. i knew that you wouldnt just have the port sticking out of the box

07-31-2003, 09:33 PM
alright that sounds good. now i just got to get access to a table saw and i'll be set