What type of port is better?

[El_dorado 0]

Sup guys I have a few questions, I've seen so many different types of enclouser's for example

Round ports

Slot ports

squared ports

port for each side individual chamber

Ok for my subs I have 2 12" dvc subs punch

my max dimm. are 34 wide x 15.5 height x 17 depth all pieces are cut out already I want to know how ??? should I make my port round, slot ported, port in between the middle. tuned around 32 to 35 hz so that's about it so can someone please lay a hand on me all info would be great thanks to all....

[Supa_c 1]

Really, it doesnt matter what side you put the port on or what type it is.

[El_dorado 0]

Thank you for the reply also do u know how long should I make my port if I go round ?about 12" or 15 " will be good I'll be using 4" round pvc ports

[Supa_c 1]

www.psp-inc.com

Use the port calculator

Its by far the best one ive seen online

[El_dorado 0]

Hey thanks for the tip it's cool to have people giving out a hand thanks again. also what if I I get port noise How should I get rid of it ?

[ANeonRider 3]

More port area.

[El_dorado 0]

More port area ? u mean use a larger port in diamm. thanks also for reply cool

[haydenlake 0]

More port area ? u mean use a larger port in diamm. thanks also for reply cool

<{POST_SNAPBACK}>

Alright I'll just run through a few things I've learned about ports.

Use calculators (typically online) to determine the length and diameter of the port.

In general a large port is less likely to give you port noise because less air is moving over a large surface area.

Port shape is realativly unimportant as long as it is consistent and smooth (try areoports I think you can get them from partsexpress.com) these types of ports are shapped like a funnel so you can actually run a slightly shorter port and have the same effective tuning (very handy in many applications)

For SQ reasons don't place the speaker direclty near the port, and don't place the port directly near a wall (unless its a slot port then it is part of the wall) (I'm not sure as to the justification behind this but people that know more than me have rec'd this.

If you're running 12's that have any decent excursion you really should step up to a 5 or six inch port. if you don't buy areoports by god at least sand the hell out of the ends so they are smooth.

remember that port displacement is measured by the total external dimensions of the port, (don't forget end factor correction) generally meaning that the port acts half the width of the port longer than the whole port tube itself. See JLaudio tutorials if you need more help.

To give you an idea of how much air good subs move. I have an IDMax 12 in a 3.2 cu ft slot ported box tuned to 27hz and a port area of 48 inches and I can feel the air moving from 4 feet away. Trying to tune this low in a box this size would be nearly imposible without a slot port.

later,

b

[ANeonRider 3]

Actually, aeroports will have to be ~1" longer...

Never have heard of any reason to have the port not near a wall, etc, unless it is because there is not enough room left between a wall, and the opening of the port.

End correction only applies to slot ports using one of the outsides of the box as one side of the port in a slotted configuration.

Port area is the outside dimensions, but has no relation to the length. Length determines the port tuning.

Port area of a round port is pi*r^2

Port area of a square port is WxL

Round ports require less port area because of the reduced surface area of the port.