Question on How to Measure Port length-2 diff. designs

[PowerNaudio 10+ year member]

yeah thats correct. but i dont see where you got the 2.25" from though

 

[Texas Tech 10+ year member]

1.5 is the distance to the center point and 2.25 is the length to one side of the port including the woods thickness (it was .75)

How far away is killeen from DFW?

 

[Texas Tech 10+ year member]

Do you always do that kind of measuring for percieved length when the distance from the end of the port to the wall is the same distance as the width of your port.

So your width is 3 inches and teh length from teh end of your port to the wall of the enclosure is 3 inches.

Because is that what you did for this...

(off of the third page)

You are commenting on my diagram that i originally posted.

about your T port. my drawing is a true T port "no baffle separating each port". your drawing is not a T port, but two L shaped ports back to back, so you would calculate your T port length and width of the port at the end of the port, just like you would for a regular L shaped port. and 12+7+1.5 is incorrect. assuming that the port end is 3" from the nearest wall and 3" wide. it would be: 12" + 7" + 1.5" + 1.5" + .75 + 1.5"= 24.25" of perceived port length

when you draw your port you don't draw the port with port end correction, because port end correction is a perceived length. its not the physical length of the port. you draw the physical length of the port. the same way it would be built.

 

[PowerNaudio 10+ year member]

Do you always do that kind of measuring for percieved length when the distance from the end of the port to the wall is the same distance as the width of your port.
So your width is 3 inches and teh length from teh end of your port to the wall of the enclosure is 3 inches.

Because is that what you did for this...

(off of the third page)

You are commenting on my diagram that i originally posted.

about your T port. my drawing is a true T port "no baffle separating each port". your drawing is not a T port, but two L shaped ports back to back, so you would calculate your T port length and width of the port at the end of the port, just like you would for a regular L shaped port. and 12+7+1.5 is incorrect. assuming that the port end is 3" from the nearest wall and 3" wide. it would be: 12" + 7" + 1.5" + 1.5" + .75 + 1.5"= 24.25" of perceived port length

when you draw your port you don't draw the port with port end correction, because port end correction is a perceived length. its not the physical length of the port. you draw the physical length of the port. the same way it would be built.

yes any time the port is the width of the port or the higth of the port which ever applies in that particular design away from a wall. you have to do what i showed you. if not the tuning will be of by a small amount.

 

[Texas Tech 10+ year member]

yes any time the port is the width of the port or the heigth of the port which ever applies in that particular design away from a wall. you have to do what i showed you. if not the tuning will be of by a small amount.

So if the height is the is the smaller length, like 4 inches in height and 30 inches in length, and the end of the port is 4 inches away from the enclosure wall you would do that as well

Well thanks for the cool info

 

[PowerNaudio 10+ year member]

yes, you would. anytime the port is the port width away from the wall the space between the port and the wall becomes part of the port, so you would have to calculate that area between them as length and displacement of the port. the reason i say hight as well as width is because some times the port is designed in a way where the hight of the port is used as the width of the port and vise versa so which ever applies to that particular system, you will incorporate the same math.

 

[Texas Tech 10+ year member]

anytime the port is the port width away from the wall the space between the port and the wall becomes part of the port, so you would have to calculate that area between them as length and displacement of the port

And when you say length. you add that to your actual physical length plus the end correction (half of the width) and you have your percieved length.

 

[PowerNaudio 10+ year member]

right