thinking of building a box

[xtullyx]

Soo.. im thinking of building a box for an alpine type r 15" or having twisted on here build one for me.. but if i decide ultimately to build one myself what calculations and info do i need? i have my trunk dimensions, if i build a box its going to be a basic rectangle but i dont know how to calculate the size of the port... the port size recommended for the type r is 1.3-3.0. the box i have in mind is width x height x depth = 20 x 17 x 20= 3.2 cu ft. thats the internal cu ft without taking out sub cubic feet. do u think thats to big or just right? and what size and shape should my port be? also the thickness of the wood is 5/8, will that be thick enough?

Click to read more...

 

[d-REW 10+ year member]

im thinking of taking a shit

 

[Twistid 5,000+ posts]

x2

 

[1rockford1 5,000+ posts]

x3

 

[xtullyx]

thanks for the help..//content.invisioncic.com/y282845/emoticons/mad.gif.c18f003ab0ef8a0d9c27ca78d77a6392.gif

 

[boomzilla 10+ year member]

3/4'' mdf will work fine, but if you have 5/8'' on hand it will work too. What I would do is have whoever is building your box come up with a port for you. Or you can run a 6'' pvc or two, and there's a calculator from PSP that you can play with to find the right tuning. I quit doing regular slot ports for now because of how difficult it is to figure it out lol. Hope this helps man.

 

[xtullyx]

3/4'' mdf will work fine, but if you have 5/8'' on hand it will work too. What I would do is have whoever is building your box come up with a port for you. Or you can run a 6'' pvc or two, and there's a calculator from PSP that you can play with to find the right tuning. I quit doing regular slot ports for now because of how difficult it is to figure it out lol. Hope this helps man.

so i should just build a sealed box and then save some room for a port to put in? Does the shape of the port have anything to do with how it sounds?

 

[xtullyx]

also what would be a good tuning frequency?

 

[boomzilla 10+ year member]

I wouldn't finish the box until I knew what port I'm using and where it's going to go. If you build it, put the sub in, you may have screwed it all up if the ports can't fit in later. The shape of the port can affect the sound, as seen with Rear Loading Horns, Transmission Lines, all those odd port shaped boxes can give it's own sound and effects. Regular L shaped ports will give you a certain range in which is loudest, depending on where you tune. Round ports made of pvc can do the same as an L port, only they need half the port volume as a standard L port, so you can save space. And the PSP (pricision port) Is a round pvc like material, but it has flared ends on both sides to reduce port noise, which is turbulence of the air in the box, meaning the port area is too small.

I think that covered some of it to give you an idea of what you can work with.

 

[Twisted_0912 10+ year member]

check ur pms i sent u a design

 

[boomzilla 10+ year member]

also what would be a good tuning frequency?

Depends on what you like, low notes (32-39hz) or the low low notes(30-25hz). Or if you wanna compete, you tune to 40-60hz or even higher.

But a good midpoint in those would be 30-35hz. I chose 30 because I like the lows, but also like the higher frequencies too.

 

[xtullyx]

is there a big difference between 30 hz to 35 hz?

 

[mazdakid 5,000+ posts]

you should be able to hear a difference in the 2 tunings