15" Fi Q

[tyler_fitz 10+ year member]

Right now i've got a box in mind for a 15" Fi Q. its at 3.8 cubic feet (with all displacements taken into account) tuned to 30 hz. my question is would two 4" round ports be enough for this box?

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[BassAce 10+ year member]

That's about 25.14 square feet or port area, I think you should go with more port area. Do you have the option of using slotted or square ports? If you need to go with round ports, I would recommend using flared ports even better would be using two 6" flared ports.

 

[tyler_fitz 10+ year member]

i could use some square ports. for the sake of symmetry, how would i tune my box using dual square ports? im lookin at something like 28 square inches per port...

 

[Weeznur32 10+ year member]

I had almost the exact same box, 3.8 cubic feet with 2 4" aero ports and an 15 Q and my sub didn't like it very much, couldnt handle as much power. I rebuilt my box using a square port with like 50 square inches of port and that helped a lot. Just my input.

 

[tyler_fitz 10+ year member]

alright, time to get less fancy with the design. plain ol rectangular box with slot ports. to calculate tuning for dual slot ports i divide the volume of the box by 2... right? and then calculate the length for each port from there...?

 

[mlstrass 5,000+ posts]

Do you "have" to do dual slot ports? One would be much easier...

 

[tyler_fitz 10+ year member]

how bout a single slot port.... but... its 3x18.5.... too narrow?

 

[mlstrass 5,000+ posts]

Port 2 1/2" x 18 1/2" gives you 46^2 which is right on for 3.8^3. And no issues with being too narrow...

 

[tyler_fitz 10+ year member]

excellent, now lets see if i can get this box built by the end of today...

 

[mlstrass 5,000+ posts]

excellent, now lets see if i can get this box built by the end of today...

That's the right attitude, build away...//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[tyler_fitz 10+ year member]

UGH its so freakin hot out. got it mostly done, just gotta put the front on and then all the finishing touches... but i dont have a day off till next wednesday //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif