Sundown Audio SA-10 1.43cuft ported

[shredder2]

Wow... when using a round... there will be less port area needed

 

[Jeffdachef 5,000+ posts]

24 sq.in. of port area. is what you need to avoid port compression. a 3" round port is 7 sq. in. so not nearly big enough.

this is soo wrong lmfao.

 

[shredder2]

24 sq.in. of port area. is what you need to avoid port compression. a 3" round port is 7 sq. in. so not nearly big enough.

So 3-3" rounds will work ?

 

[BOOMINGRANDPA 5,000+ posts]

what do you recommend? as this is the only box design that will work and size

u can ignor that.. what he means in slot ports need to be 12-16 sq in per cf but round ports can be as small as 6 sq in per cube

 

[BOOMINGRANDPA 5,000+ posts]

So 3-3" rounds will work ?

no shredder saying what i just said

 

[aeroportspwn 10+ year member]

with aero ports 6-10 square inches of port area per cubic foot of box "in general". I normally used that formula in the past and it worked quite well.

 

[THATpurpleKUSH 5,000+ posts]

7-11 sq inches for round ports, they are more efficient and don't need as much area. The SA 10 on 1200w is right on the border for going up to a 4 inch port, but the required length is going to be longer and harder to fit the design.

 

[ckeeler11]

Care to expand on why you think that is so wrong??

 

[ckeeler11]

How did you determine that? aeroports are at most 30% more efficient than a slot port.

 

[aeroportspwn 10+ year member]

^if you go too big of port area when using aero / round ports it can make it sound peaky as it will be pushing out too much air. Certain frequencies will sound muddy or like crap. The only time a huge port area is okay imo is when you are trying to get the biggest numbers possible doing burping or burp farts. Normally people that do that are pretty knowledgeable and also find out what the vehicle they are working with peaks at.

 

[shredder2]

How did you determine that? aeroports are at most 30% more efficient than a slot port.

Its true... 30% more efficent but it acts different too.... its like the air has pressure and the increased compression matters less due to the decrease in wall area... sorry, its something I struggled with as well at first. A round, square, aero and slot all have different characteristics and optimal applications... here is a discussion from awhile back that got me interested in finding out more....

http://www.caraudio.com/forums/enclosure-design-construction-help/547687-slot-ports-vs-aeroports.html

This might not be the answer you're lookin for but it is a decent thread... lol

 

[ckeeler11]

Compression is compression if its there it affects output. It does not matter whether it is a square, round, oval, or octagon. Round ports are more efficient than square and true Aeros with flared ends are even more efficient because of the flare reducing turbulence in front of the port, but if compression is present it is affecting the output. I used WinISD and another calculator to calculate what the OP needs. The other calculator was done by someone that did testing to verify information. It follows pretty closely to WinISD that just uses a mathematical calculation. The biggest factors to influence port area are Power, Box size, and Tuning.

Not sure if it is okay to post links to other forums but here are some references that actually explain whats going on. If this is not welcomed then the Mods please delete.

http://www.bodziosoftware.com.au/PORTS.pdf- whats interesting here is they see port compression at 100 watts on a 6" port now the affect is very small but think of what it would be for a 3" port on 1000 watts. I bet you will lose close to 5 db's of output. Might as well run a sealed enclosure.

https://www.stevemeadedesigns.com/board/topic/189867-understanding-ports-a-lesson-in-dimensions-vs-efficiency/

https://www.stevemeadedesigns.com/board/topic/209127-triticums-improved-port-area-calculator/

 

[BOOMINGRANDPA 5,000+ posts]

yeah the taller the port wall is and narrower the port width is the more port noise/compression u will have.. so a slot port 18" tall x1" wide isn't good even a 4x4 square port would probably be better even though it's less area.. round can't just be smaller, all that said 3" port on 1k sounds tad small to me too but idk 10's..

 

[shredder2]

OP... what length and volume did you end up with?.. I just got home in front of the computer and the 3", 13.6"long port in a 1.43ft3 net looks like a 28.98hz tune...

And for your power its a little high on port velocity for my liking... thats in m/s btw... lol

Now the same 1.43ft3 net with a 4" round 18.75" long will tune at 32.98hz...

This is a little better, I'd go with this anyday... flare the ends and youll be fine

That 3" port would be fine for a 700 watt amp IMHO

 

[aeroportspwn 10+ year member]

parts-express.com sells the Precision aero ports with flared ends.