Question about port and common walls

[Pyrofan]

This box is for a S10 taking 3 15's and this port will be the death of me. So I have a few questions.

1) can you curve a port with 1 common wall?

2)Would subs forward and port up sound bad? I got 40.5 in of height and the box right now is only 35in so would that be enough for the port to vent right?

3)Would a port thats 3in X 43.5in with a length of 25 sound bad ( aka Make noise). I was told it would but have seen pics of sub walls with the same size ports. Its giving a port area of 15.28 per foot.

I only have 15in of depth so im not sure what to do.

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[Pyrofan]

And sealed isnt a option.

 

[Pyrofan]

Why have so many threads gone un-replied. I it seems like a simple question to me

 

[T3mpest 10+ year member]

This box is for a S10 taking 3 15's and this port will be the death of me. So I have a few questions.
1) can you curve a port with 1 common wall?

2)Would subs forward and port up sound bad? I got 40.5 in of height and the box right now is only 35in so would that be enough for the port to vent right?

3)Would a port thats 3in X 43.5in with a length of 25 sound bad ( aka Make noise). I was told it would but have seen pics of sub walls with the same size ports. Its giving a port area of 15.28 per foot.

I only have 15in of depth so im not sure what to do.

1. Don't see a reason why not

2. Generally sub up port side firing is more common, I've never done a ranger install, lots of people have though, maybe they can chime in

3.. That's WAY to skinny to be that long.. The issue is when a port begins to compress it will have turbulence along the edges.. In your case most of your port area IS right along the edges.. So when the port compresses even a little bit it eats into your port area causing even more compression, viscous cycle and a port that size will NOT behave like a more square/ round port of similar area.. If your using a rectangle to no higher than an 8 to 1 ratio. so if the port is 3inches wide go no wider than 24 inches and if it's going to be 43.5 longthen you need to be around5.5 wide. This ratio of total port area vs edge surface area is why areos are more effecient, just as some added info. It minimizes surface area of the walls of the port while maximizing radiating surface area of the port itself. Best ratio is a circle. In your case, both those extremes probably don't fit.. Widen the port out some and shrink it's width to match.

Also feel free to PM me about anything speaker related, I don't come on here often, but I always check my PM's when I do.

 

[Pyrofan]

1. Don't see a reason why not
2. Generally sub up port side firing is more common, I've never done a ranger install, lots of people have though, maybe they can chime in

3.. That's WAY to skinny to be that long.. The issue is when a port begins to compress it will have turbulence along the edges.. In your case most of your port area IS right along the edges.. So when the port compresses even a little bit it eats into your port area causing even more compression, viscous cycle and a port that size will NOT behave like a more square/ round port of similar area.. If your using a rectangle to no higher than an 8 to 1 ratio. so if the port is 3inches wide go no wider than 24 inches and if it's going to be 43.5 longthen you need to be around5.5 wide. This ratio of total port area vs edge surface area is why areos are more effecient, just as some added info. It minimizes surface area of the walls of the port while maximizing radiating surface area of the port itself. Best ratio is a circle. In your case, both those extremes probably don't fit.. Widen the port out some and shrink it's width to match.

Also feel free to PM me about anything speaker related, I don't come on here often, but I always check my PM's when I do.

1)Ah, now some good info. So i can just make a smaller port with 1 common wall and curve it down along the back of the box.

2)I would do subs up be i dont have enough room and he wants to see the subs firing.

3)I was worried about that but now i think i think what to do.

EDIT: Here is a quick sketchup design. Port of 5x25 length of 20. Tuned to 35Hz and area per foot of 14in. Thats with 1 common port wall.

 

[Pyrofan]

can someone chime in and say if that will work?

 

[Pyrofan]

Well, did some research and dont see a problem with this box, but thats why im on here. I wanna make sure it will work. Someone said that doing this make the port sound "weird". Any truth to this?

 

[bbeljefe]

I don't like that the center sub is so close to the mouth of the vent. You could cause that sub to unload but it's hard to say without seeing a perspective from the front with measurements.

 

[Pyrofan]

I don't like that the center sub is so close to the mouth of the vent. You could cause that sub to unload but it's hard to say without seeing a perspective from the front with measurements.

I can get you measurements tomorrow morning. I dont wanna make it wider so that sub cant go any lower. It 35in high x 45 in length so you might can get a rough estimate from the pic

 

[bbeljefe]

Well, you could always reverse the way the subs are arranged. That would put them closer to equidistant from the mouth of the vent.

 

[Pyrofan]

Well, you could always reverse the way the subs are arranged. That would put them closer to equidistant from the mouth of the vent.

That might would work. Besides the sub placement, the box should work?

 

[bbeljefe]

That might would work. Besides the sub placement, the box should work?

I don't see why it won't.

 

[Pyrofan]

I don't see why it won't.

Oh thats good

 

[Pyrofan]

The problem is, i cant move the subs higher. The seat will block them.