Aero ports and distance from perpendicular wall inside enclosure?

[DiBo]

How far should an aero Port be away from it's perpendicular wall inside the box? 6" aero = 6"? 8" aero =8"?... Etc. Seems to me a 6" should be maybe 3" away. 

[MyNameIsNoob]

That's a good question bc I'm ab to build 3 boxes w 2 12s each w aeroports... (I'm thinking out loud), but I'd think since it's not confined to a wall n it can breathe in multiple directions it would be able to be closer than a slot port as long as it can displace the port area... ?... I'd love to know myself tho.

[MyNameIsNoob]

Found this and a cpl other articles. Says it should be equal distance of port diameter. 

http://ddaudio.com/ddownlow/july-tech-talk-breath-easy-making-ports/

[DiBo]

49 minutes ago, MyNameIsNoob said:

Found this and a cpl other articles. Says it should be equal distance of port diameter. 

http://ddaudio.com/ddownlow/july-tech-talk-breath-easy-making-ports/

Seems to me that a 12" Port needing to be 12"away seems extreme. I'm not fond of aeroports anyways. I prefer slot ports all day. I was asking for someone else. I'm going to do some testing eventually and see what I come up with

[MyNameIsNoob]

44 minutes ago, DiBo said:

Seems to me that a 12" Port needing to be 12"away seems extreme. I'm not fond of aeroports anyways. I prefer slot ports all day. I was asking for someone else. I'm going to do some testing eventually and see what I come up with

That's prob the best way to go anyways. What sounds best to my ears is what I want

[ToNasty]

My understanding is half the diameter of the port width.  6" port would need 3" clearance

[Triticum Agricolam]

1 hour ago, DiBo said:

Seems to me that a 12" Port needing to be 12"away seems extreme. I'm not fond of aeroports anyways. I prefer slot ports all day. I was asking for someone else. I'm going to do some testing eventually and see what I come up with

So the thing to keep in mind is how far away from a wall a port needs to be before bad things happen is different then how away from a wall a port needs to be ANYTHING happens.  

If you don't want ANYTHING to happen, then yeah keeping the port at least one port diameter away is the best practice.  So what happens if its closer than that?  You will begin to affect the tuning frequency, most likely lowering it.  As you get closer still eventually you will start to obstruct the port enough it will decrease output/make a bunch of port noise.  A port only has to be 1/4 the diameter away for the area around the end of the port to be equal to the area of the port itself.  Now I'm not saying you should only make the port 1/4 diameter away, but that's how close it can get before you decrease the effective area of the port.  I would expect you would start to have degraded performance before that point though due to the air having to make an abrupt change in direction.  

If you have to put a port close to a wall there are things you can do to help the air flow better and reduce the effect it will have on tuning.  Google "polk power port" for some interesting ideas.  

[MyNameIsNoob]

54 minutes ago, Triticum Agricolam said:

So the thing to keep in mind is how far away from a wall a port needs to be before bad things happen is different then how away from a wall a port needs to be ANYTHING happens.  

If you don't want ANYTHING to happen, then yeah keeping the port at least one port diameter away is the best practice.  So what happens if its closer than that?  You will begin to affect the tuning frequency, most likely lowering it.  As you get closer still eventually you will start to obstruct the port enough it will decrease output/make a bunch of port noise.  A port only has to be 1/4 the diameter away for the area around the end of the port to be equal to the area of the port itself.  Now I'm not saying you should only make the port 1/4 diameter away, but that's how close it can get before you decrease the effective area of the port.  I would expect you would start to have degraded performance before that point though due to the air having to make an abrupt change in direction.  

If you have to put a port close to a wall there are things you can do to help the air flow better and reduce the effect it will have on tuning.  Google "polk power port" for some interesting ideas.  

That's pretty interesting. I wonder how much it would help if you only put a reverse flare centered w an aeroport on back wall vs the way theirs is w the pole piece through the center?