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Featured Replies

Posted

when you build a box with a square or round port, isnt it nearly impossible to stay within the 12-16 sq in of port area per cube rule? if so what is the rule for those? and when making a external port it is still the same length as if it would be internal correct, only it is on the outside...

There is no difference between square, round, and L-shaped. L-shaped just refers to if the port is too long to fit the depth of the box and you have to angle the port another direction to get the required length for the tuning you need.

If you have a 12" deep box and need a 15" port, you make it L-shaped. If you only need an 8" deep port, you don't. Simple as that.

As for internal vs. external, yes they are the same length because the volume of the box for the subs doesn't change. You just may be able to make the box 4 cubic feet gross instead of 5 cubic feet if you make the ports external because you wouldn't have port displacement.

  • Author

can you make a port that is part internal and part external...such as 5 inches external and 12 inches internal to get a certain frequency rather than L-ing it?

and what is total port length bc on the re site calculator it will something like port 1-12 and port 2-3, and then the port length will be like 19...so how do you figure out how long to make the port

Edited by loondizie52

Yes having 5 external and 12 internal is fine. Just have to remember to account for the displacement of the port that's inside of the enclosure.

the RE calculator tells you how long to make each piece of the port. The long piece, towards the back, would be 12" long. The part that comes off and creates the L, parallel to the back wall, is 3". But since you measure down the center of the port and into the center of the corner, the total length becomes 19". I assume your port is 4" wide?

  • Author

well i was just throwin some numbers out as examples but i understand much better now...so you measure down the center to the center of the corner then till the end of the 2nd L correct?

Here's A Better Question. Where The Hell Did You Get Two Of Only 24 Woofers Ever Made, And How Much Do You Want For Both?

There is no difference between square, round, and L-shaped. L-shaped just refers to if the port is too long to fit the depth of the box and you have to angle the port another direction to get the required length for the tuning you need.

If you have a 12" deep box and need a 15" port, you make it L-shaped. If you only need an 8" deep port, you don't. Simple as that.

As for internal vs. external, yes they are the same length because the volume of the box for the subs doesn't change. You just may be able to make the box 4 cubic feet gross instead of 5 cubic feet if you make the ports external because you wouldn't have port displacement.

wrong there is a difference

each turn in the port causes turbulence

slot(square ports that use one side of the box as a port wall)

usually are very good with noise because of the opening of the port being easy to load and not have air being blown across the opening

square ports that don't bend

have less turbulence but may have more pressure blow by

round ports

are the worse until they are flared thats why they are the noisiest

now if you use any of these and flare them it helps alot by creating a void and helps pull the air out of the enclosure

more air movement = more db's (most of the time )

now are any of these differences enough to hear by ear?

most of the time no but on the meter there is a difference

I just thought you should know this in case you want to compete

and don't use re's calculator it is often way off

Edited by wenn_du_weinst

There is no difference between square, round, and L-shaped. L-shaped just refers to if the port is too long to fit the depth of the box and you have to angle the port another direction to get the required length for the tuning you need.

If you have a 12" deep box and need a 15" port, you make it L-shaped. If you only need an 8" deep port, you don't. Simple as that.

As for internal vs. external, yes they are the same length because the volume of the box for the subs doesn't change. You just may be able to make the box 4 cubic feet gross instead of 5 cubic feet if you make the ports external because you wouldn't have port displacement.

wrong there is a difference

each turn in the port causes turbulence

slot(square ports that use one side of the box as a port wall)

usually are very good with noise because of the opening of the port being easy to load and not have air being blown across the opening

square ports that don't bend

have less turbulence but may have more pressure blow by

round ports

are the worse until they are flared thats why they are the noisiest

now if you use any of these and flare them it helps alot by creating a void and helps pull the air out of the enclosure

more air movement = more db's (most of the time )

now are any of these differences enough to hear by ear?

most of the time no but on the meter there is a difference

I just thought you should know this in case you want to compete

and don't use re's calculator it is often way off

That's all fine and dandy, but that's not the issue. If you have a 12" deep box but need an 18" deep port, what are you going to do?

round ports

are the worse until they are flared thats why they are the noisiest

now if you use any of these and flare them it helps alot by creating a void and helps pull the air out of the enclosure

WTF

Edited by BloWNMind

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