Little help

I know my pics suck but not the point, this is what I have to work with need help on what size port to do and how long let's see sone of u big box builders help out, port can go on the top where it is 14"x38" port can only be 7"x33 max and 19" length but u tell me what size I need for a tuning in upper 50's or something to use as a burped thanks ask questions if needed(that pertain to box in a helping manner)

20-25 sq inchs of port per cubic foot, 15" long

No room for that much most is like 18" per and If so is it best to relocate port to back plate on the 25" side cuz I can

jonatan wrote:

No room for that much most is like 18" per and If so is it best to relocate port to back plate on the 25" side cuz I can

Hard to tell you anything really considering we don't know the sub, what its going in or the location in said vehicle.

The woofer will tell us what net you actually need to use. The the port area will be off the net airspace and desired response type. You will want large as rob said for a burp box. Also the woofer would be nice to know for how it will react to said port area. Leaving use to our last thing the vehicle and placement of enclosure so we can then get tune optimal for vehicle and desired frequency response.

So ask lol, dd9518's in a 4runner behind rear seats

I would start at least 6 net per with 240 sq.in of port for a burp machine. If it is going in the cargo area of that vehicle upper 50s is way too high on tune for it. What amp will be used? If its not a big amp more going larger on enclosure will make it more efficient.

If u look at what I gave as measurements that will tell u the qft and how long will port be I have the port area down just not length I'm thinking from 15"-19"

Plus I can do that much port area on top plate so seal it up and cut port else where? Where would be best for port to be

yes your measurements will give me airspace, but Gross. To figure net and be able to figure the actual sq.in of port. allowing me to be able to figure tune I first have to take away the driver displacement, any bracing and port displacement. Then you have your net which you can figure your port area off and also the port length which will tune your FB.


You also didn't say where this will be located. You said this is for burping. If it is in the rear cargo area upper 50s is too high. Hell 50s period is probably too high of a tune. Im sure if in cargo area it will should peak somewhere in the mid 40Hz range for vehicle resonance.

50's is to high??? Yea I told u where and what, and yes I know net air I need most help with port length and where it would be best on box