port displacement help

[atlninja82 10+ year member]

hey guys,

im trying to find out the dimensions i need to make my box so i can have around 2.5 net cubes. the subs take up .14 ft^3 together and now i just need to figure out the port displacement. do i only subtract the piece of wood made for the port? so does the actual port area count as box volume as well or is that whole port area subtracted?

also i drew up a quick sketch of the box. does it look like this port will have too many turns and cause port noise because of it or is it ok?

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[ahole-ic]

I know you just want your question answered, but why exactly did you design the box that way?

Port area does not count as box volume. Also, it becomes very difficult to calculate port length and thus tuning with that many bends. It's best to only have 1 bend in your port. Redesign time.

 

[atlninja82 10+ year member]

welll im building this box on top of the middle seat in the back in my 4 door truck. anyone got a better design than this? well i dont have a probem tuning the box or calculating the port length i just need to know how to find the volume of the box with the port there

 

[ahole-ic]

welll im building this box on top of the middle seat in the back in my 4 door truck. anyone got a better design than this? well i dont have a probem tuning the box or calculating the port length i just need to know how to find the volume of the box with the port there

I mean no offense, but you have your port length already designed yet you don't know the enclosure volume. Enclosure volume is 1/3 of the equation so if you don't know it, you can't possibly know your tuning. To calculate the available area, you need the inside dimensions and you divide it up into different rectangles. Then add them together.

 

[marcotheclepto 10+ year member]

hmmm i can help you with a design and as stated port volume does not include the volume of the box. as ecrack said volume of box is very important to the tuning the rectangle suggestion works very well.

 

[atlninja82 10+ year member]

ahh this shit is confusing. I need 2.5-3 cubes net. port area needs to be around 50 sq inches. max dimensions are 15 wide 24.5 long and can be as high as needed. the bottom half max dims are 8 high 10.5 long and 15 wide. subs takes up .14 cubes together. if anyone wants to help me out with a design id really appreciate it

 

[atlninja82 10+ year member]

and i want it tuned at around 34-35 hz