Box for 3 12's, Aeroport

[fyerbyrd22]

gonna be more port area and imo, on the edge of too much port...but i think it should be fine

[Triticum Agricolam]

do not put an 10" aero in a 5cu box..the amount of subs is irrelevent..its net cubic airspace that u worry about for port area...an 8" will be perfectly fine, at 10sq per cube vs 15sq per cube...its an aero so u dont need as much port area as a slot

Port area per cube rules need to go away. There is so much more to determining proper port area than just net volume.

gonna be more port area and imo, on the edge of too much port...but i think it should be fine

Please, tell me what you think happens when there is "too much port".

I would love to put an 8" port in there but I really cant afford spending $150 on a elbow to curve my port. I only have 14"h so the port has to bend. So would two 6" ports be ok? I know it is not ideal but I can't be to choosy with such a little box.

Two 6" ports isn't going to be any better than one 8". For what you want to do I'd just go with a slot port. Get about 75 sq in of port area and that should work well.

[Miguels]

I look at a sig and see quality boxes. Then watch a video with a nasty box. it does get loud but watching the video and looking at the sig with quality box. I think I know who's advice I would take

[fyerbyrd22]

port area per cube is a general rule of thumb but no where near accurate in some cases...and too much port makes the box peaky, causes unloading faster...idk where people are getting this idea to use huge aero ports with the same port area as a slot...its going to fail...period...unless its a burp box, its going to be peaky...and idk who that above comment was aimed at...look at my sig and go to my page and youll see my most recent work...quality boxes, no garbage

[Miguels]

Common sense will tell you it wasn't aimed at you since you never posted a video on here.

[Triticum Agricolam]

port area per cube is a general rule of thumb but no where near accurate in some cases...and too much port makes the box peaky, causes unloading faster...idk where people are getting this idea to use huge aero ports with the same port area as a slot...its going to fail...period...unless its a burp box, its going to be peaky...and idk who that above comment was aimed at...look at my sig and go to my page and youll see my most recent work...quality boxes, no garbage

I looked at your facebook page. Your boxes look nice and appear to be decently well constructed. Unfortunately though you have been misled by some common car audio misinformation.

Making a port larger does NOT make a box peaky, making the box larger does. The gain you get around the tuning frequency with a ported box comes from the size of the box. Make the box too big and you get too much gain = peaky box. The only thing the port can do is negatively effect output by restricting airflow if it's too small.

Making a port larger does NOT cause unloading faster, ported boxes unload when you play below the port tuning frequency. Assuming the tuning frequency is the same, a large port is going to unload the same as a smaller one. In fact, if a port is too small it will increase cone excursion at high volume (have less cone control as some call it) because the box begins to act as a leaky sealed box.

[fyerbyrd22]

I haven't been mislead by anything...I know it from experience...putting the same amount of port area u would use from a slot port into a box with an aero will not perform well daily..period...aeros are more efficient so they don't need nor want that much port area..every box/sub combo is different but yes, a safe number for aeros is between 6-12sq per cube...had my 4 12s doing over a 50 on less than 3k at 33hz...8sq of port per cube

[Triticum Agricolam]

I haven't been mislead by anything...I know it from experience...putting the same amount of port area u would use from a slot port into a box with an aero will not perform well daily..period...aeros are more efficient so they don't need nor want that much port area..every box/sub combo is different but yes, a safe number for aeros is between 6-12sq per cube...had my 4 12s doing over a 50 on less than 3k at 33hz...8sq of port per cube

Well you seem pretty convinced in your "knowledge" so I don't have any delusions that I'm going to change your mind on anything, but in the interest of informing whomever else may read this thread, I'm going to continue on.

You are correct that aero ports are more efficient, they take up less volume for the amount of port area they have, and they tolerate slightly higher port velocities than slot ports do. However there is no performance difference between them and a slot port as long as both are adequately sized for the application in which they are used.

Just a couple posts ago you agreed that "port are per cube" rules aren't accurate, but now you are quoting them again. Generalizations like that are a bad way to do things because they doesn't have any consideration for:

1. Tuning frequency - higher tunings generate higher port velocities and need more port area

2. Power input - Obviously a 200 watt sub doesn't need the same port area as a 3000 watt sub just because they are in the same size box

3. Differences between subs - different subs have different specs, some are more efficient than others so they all are going to have somewhat different port area requirements regardless if other aspects of the installation are the same

4. Differences in port implementations - obviously a straight port with no obstructions and a low aspect ratio is going to handle high port velocities a lot better than one of equal area, but has three 180 degree bends in it and/or has a really high aspect ratio

When it comes to sizing ports, it's a lot like sizing power wire for an amp, it's either big enough to do the job right or it's not. Once you have a big enough wire/large enough port to not negatively impact performance, making it larger will not change performance one bit. Nor is there any performance disadvantage to making them larger, they would just cost more/take up more space. So, referring back to your example, if you had a box with an adequately sized slot port and you changed it to aero port/s of equal port area, keeping everything else the same, there would be NO DIFFERENCE in performance. If there was a difference that just means that your slot port wasn't actually adequately sized in the first place.

It is extremely difficult to have too much port area. If having too much port area with aero ports created a problem like you said, there would be a lot of boxes out there that sound great at max volume, but then would sound bad when you turned the volume down and the port velocities dropped.

[fyerbyrd22]

U can try to justify it and explains it better but it's irrelevant..there is such thing as too much port...you're the one clearly stuck in your ways...I'll put money in it that I'm right..and I did say before that there are factors but s good generalization is what I said...every sub is different, every box is different..but if you're gonna continue to say that there's no such thing as too much port and u want the same amount of port for a slot as u would with an aero, keep misinforming people

[scooter99]

This is an interesting conversation.

Dude, op, save yourself the heartache and do a sealed enclosure!