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Sub Boxes, Finally Explained...

Ported; Uses a larger box that has one or more openings in it to allow the sub to continue to move after it hits, making it "pulsate", (think of a guitar string) the free air in the box is the same pressure as the air outside of the box so that there is nothing other than the speaker's mechanics to pull the cone back in.



Sealed; Uses a smaller box that has no openings so that the air inside of the box is a higher pressure while playing. When a subwoofer in a sealed incloseure hits, it hits hard and then the cone is sucked back in by the higher pressure of the box, allowing it to play the tight punchy bass more accurately. But when it comes to music that the bass "rings" after it hits it won't play as well.


There are also bandpass boxes too, I know that they use a sealed box also but go another step further and enclose the area infront of the cones too.

If I have any information wrong feel free to correct me.

From experiance, I know that too big of a box will hurt not only your music but it reduces your sub's life too.

thestranded wrote:There are also bandpass boxes too, I know that they use a sealed box also but go another step further and enclose the area infront of the cones too.

yes an no. bandpass boxes also use a port for the front of the sub and seal the back.

So, if the Sub box has holes in it to let air come into the sub, it will sound better.

Good advice, thanks

specific sized 'holes' in the box. Not just a guy with a hole cutter

Theres a LOT more to it then that, the "holes" or ports as there called need to be tuned to a spesific frequency, this helps amplify the sub at its lower frequenceys to make the frequency curve flatter.

Generally the sub will be the loudest at the port frequency.

Bandpass boxes are only "good" if you only listen to one type of music, so you can tune the box to that type of music.

There are many websites that will help you design a bandpass box and give you the proper specs of the ports that will provide the optimal performance out of the certain subwoofer

To calcuate all this you need to know the T/S parameters of the subwoofer, wich are generally provided by the subs manufactuar.

All this holds true to a ported box as well.

As does it to a sealed box, without the port part obvisouly.

Make sure you do your research before making a box, its deffently worth it.

Bochek