How much room I need to leave in front of a port ?

[Notorious97200 339]

Hello ,

I am building a box with a round port. I'll try to flare the openings to have a nice flare port

It will be a 6" port or an 8", I don't know yet !

 

How far from the box side can I have the port ?

How much "room" does it need to play correctly, safely ? I know I can use an elbow, and I will if it's necessary.

 

Thanks in advance for your advices.

 

[///M5 2,833]

If it is on the side why not just build a slot.  You can still flare it if you like to reduce the overall needed area.

[jonbearsmt 919]

i only have about 4 inches   from my port to my trunk wall

[djjdnap 78]

i looked this up a while ago i kept reading.

 

atleast half of your port length.

so if your port is 6" long you need atleast 3" from whatever(hatch, wall, ect)

[Notorious97200 339]

Port length is 8".

But I am talking about the space in front of the port IN the box.

Box is 16" tall. 3/4" mdf

So : 14.5 - 8 = 5.5" in front of the port(the air entry) in the box.

Is that enough ?

If not, I will have to use an elbow.

Port is firing up. No problem, there is room.

[Notorious97200 339]

The slot flared port is another idea.

I'll think about it.

But I can adjust the round ports easier.

[edouble101 314]

i looked this up a while ago i kept reading.

 

atleast half of your port length.

so if your port is 6" long you need atleast 3" from whatever(hatch, wall, ect)

 

It isnt half the port length but rather half the port diameter I have even read some references that claim a distance equal to the port diameter.

 

Port Flares

 

 

 

The slot flared port is another idea.

I'll think about it.

But I can adjust the round ports easier.

 

 

Fared ports are typically made out of a plastic material. Slot ports are normally made out of the wood you are building the box with. Port fares can be a weight savings.

 

IIRC I read a study where the author proved that the air velocity was less with a flared round port tube compared to a slot port with equal surface area. So this means that you can have a smaller fared round port tube compared to a larger equally performing slot port. This is beneficial for reducing port length which reduces net enclosure size and helps reduce overall weight. I also think that enclosures using flared round ports are easier to build.

[Notorious97200 339]

It's what I thought, edouble101.

I need all the room I can save for the DD9515 : it needs box volume. I am getting 3.8 ft3 net, at 35 HZ.

RAM designed the box for me, but I wanted to check some things, here !

 

He told me that I would not need elbow; with the height of the box, and the port length.

 

Thanks, guys.