Why use ports? Confused about what I've read....

[will77530]

whoever said to put a fourth order behind the seat is talking out there ass if you dont have a lot of space this will not work fourth orders require a lot of space along with sixth orders,,,,,if you want to do a blow through you can and it can be a ported box it may act like a fourth order though

[ChevyBoy95]

You get increased db at the tuning frequency.

no...

you can tune to a certain frequency with the idea of playing notes better around that target frequency, BUT due to cabin gain and other factors, tuning to say 35hz might make your loudest notes to EAR in the upper 20s and mid 40s, and a dip in the mid 30s, and vise versa. The number you are tuning too almost becomes irrelevant once the box is in the vehicle, if that makes any sense.

edit: sp*

[vrollin]

Yes it was, but to do it behind the seat is nere impossible

You'll need 60lts gross volume to do a single 10" ported in 28lts net at 32-33hz

And to fit that in with the trans tunnel in the way won't give you much room to do the port

The only way I've ever done it was a box like your but sealed all the way accross to make 1 box(not 2like yours) and run 2x 75mm external aero ports straight up the back window firing at roof

Another thing to look at is most sub require 50-60% more net volume to go ported over sealed

Then you need to take into consideration the port, and the smaller the net volume of the box the longer the port needs to be,

A 30ltr box with say a 90cm^2 port will require close to 115cm long port at 32-33hz

You see what I mean now

Internally my boxes are just over 20L each, which is about the right volume according to the focal specs to be ported at, I pretty much just went for that volume based on no science when building them because that's what I could get to fit and seemed legit, which happened to be one of Focals suggested ported enclosures. From what youre saying the ports would need to be longer than the boxes i have for their volume? Im so fucking lost....

[vrollin]

whoever said to put a fourth order behind the seat is talking out there ass if you dont have a lot of space this will not work fourth orders require a lot of space along with sixth orders,,,,,if you want to do a blow through you can and it can be a ported box it may act like a fourth order though

Not sure how a fourth order works haha :S

[will77530]

a fourth order has a sealed side and a ported side basically two boxes in one

[412 CVX]

Jesus... don't start talking about bandpass, he asked about ported. When designed right, ported almost ALWAYS is louder. I've heard both sealed and ported. The myth that ported is punchier and sloppier is just not true. When designed right, they can both have very flat responses.

Most people run ported because there is usually a considerably greater output. just overall better bang for your buck. A lot of people say it sounds better too.

[john253a]

whoever said to put a fourth order behind the seat is talking out there ass if you dont have a lot of space this will not work fourth orders require a lot of space along with sixth orders,,,,,if you want to do a blow through you can and it can be a ported box it may act like a fourth order though

im talking about the rear, different term to the usa, yous say bed, if you look as his build youll bee what i mean,

to do 4,6 or 8th and only put aero ports through cabin rear wall

as for blow through, there an illegal modification in australia, with out engineers report (cost $800+ to get one) and it will probably never pass, another option is to have an IVC done ($3500+), to be done basically requires the crash testing of a same vehicle to see the effects of the modification (our laws over here are very strict)

so on his vehicle blow through is out of the question,

4th in bed ported into truck is doable

or external ports, with 20ltrs net a psp 17" (18" or 45.7cm) port will give him 38hz (and if gross 40hz)

with a 3" 75mm aero youll need 30" 76cm per box to be in the low 30's

either way not looking good for his car

[Colin - STAPUFT]

I was once a fan of sealed boxes.... oh the error of my ways.

Ported owns in output, bass extension, and SQ over sealed IF (get it? that is a big "if") you do it right.

[punkrockprs]

once you go ported you never go back

[Socky]

I perfer a ported box over sealed, just because of the output and response. Yes sealed has a very nice bandwidth, but a proper ported box will have the same if designed correctly, its all in the design, test, and test some more to find the box that suits your taste.