Porting

[Virtual_Unknown]

can you add a port to an already built and sealed sub box?

also, how do you find the best place to position the port and what the correct length of the port should be?

 

[blink172]

Dont think so mate, think they are different proportions. if you search the net there are programs you can use to design one for you, but cant remember the names.

Ian

 

[Virtual_Unknown]

im checking on talkaudio.net but those guys know how to confuse people! lol

 

[Barryd]

You can add a port if you like, it will sound worse though as ported boxed need to be bigger than sealed ones. Unless youve build the box yourself and its too big!

 

[Virtual_Unknown]

how much bigger than a sealed box does a ported box need to be in volume - and does anyone know about the positioning of the port

 

[Evil ICE]

There isnt an exact figure as to how big the box should be if you are going ported over sealed as it depends on many things. programs like Win ISD will tell you most things but only if you know enough spec about the sub e.g. fs, QTS, VAS etc etc. It can get very confusing and ive never really got on with it.

With port placement, you should usually try to put it on the side that the subs face and the port itself should always be longer than the depth of the sub. If you are just planning on sticking one of those round Autoleads plastic things in then dont bother. You will need to modify your box (not impossible) or make a new one to incorporate a slot port for best results.

What sub have you got...it might not suit ported boxes.

 

[absentmat]

if you bought the sub-box as sealed then keep it that way.

if you bought the sub an box seperate you might have the wrong type of sub (there is a diffrence) thats why it might sound poo.

http://erc.qmuc.ac.uk/cliosport/gallery/full/1083089280__sealed.jpgSealed boxes: For deep, precise bass
A sealed box is an airtight enclosure housing your subwoofer. A sealed box is best for any music that demands tight, accurate bass. Expect flat response (not excessively boomy), deep bass extension, and excellent power handling. Since a sealed enclosure tends to require more power than a ported box, use an amplifier with ample wattage for optimum performance.

http://erc.qmuc.ac.uk/cliosport/gallery/full/1083089362__ported.jpgPorted boxes: For forceful bass
Ported boxes use a vent (called a port) to reinforce low bass response. You get more output than you would from a sealed box at any given amplifier wattage. Some people prefer the sound of ported boxes for rock, heavy metal, or any hard-driving music. Ported boxes can deliver deeper bass than sealed boxes, though they need to be much larger than sealed enclosures to accomplish that.

http://erc.qmuc.ac.uk/cliosport/gallery/full/1083089454__4thordbp.jpghttp://erc.qmuc.ac.uk/cliosport/gallery/full/1083089481__6thordbp.jpgBandpass boxes: Maximum slam!
Bandpass boxes are a special type of ported box designed for maximum slam. The woofer is mounted inside a dual-chambered box (one chamber sealed, the other ported), with the sound waves emerging from the ported side. The sound that comes out of the port is extra loud within a narrow frequency range.

Because bandpass boxes are super efficient within that range, they tend to boom. Their aggressive sound is great for rap, reggae, and hard rock. Not all subwoofers work well in bandpass boxes, though; consult our product information or call a Product Advisor to be sure.


hope it helps... matt (manchester cup)

 

[Virtual_Unknown]

awsome guys - cheers