okay i'm building a box well my uncle is gonna build it for me i just need to tell him the dimensions? how would i go about finding the dimensions of a 1.4cu.ft box with 3"Dia(76mm) x 35' (89mm) port? its for a 12 inch sub

What are the max dimensions of your vehicle and what thickness of wood are you using?

What subwoofer are you using for this application? What is your desired tuning frequency of the box? Using that port length and diameter lands you around 37HZ.

the subwoofer i'm making it for is a pioneer ts-w3001d4 i'm thinking with a 1 inch thikcness (not sure how much they come in) i can it 16" height 18" width and 14" depth

with that i'll be at 1.55556 cu.ft and the max recommendation for this is 1.6 cu.ft

but i'm confused about the port... is it a circle port? because its says for the port
3"Dia.(76mm) x 2.5"(64mm)

so is that 3 inch diameter and 2.5 inch long?

BTW..... what kinda wood would be best to make it with?

thanks for the replys

MDF is the best or birch. You might be able to find 1 inch depending on where you are. if not just get 3/4 and double up the front. And yes it is a round port. You can make the box almost twice the size if you want just dont put too much power to it. Also the port is the correct recommendation.

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NORTHERN AUTO SOUND

width 20" height 15" depth 13" thickness 3/4" = 1.66211 the max vol is 1.6 cu.ft but the support inside box will even it out
the subwoofer part that is inside the box is 7-1/2 leaving 4-1/2 behind the sub
are these dimensions okays?

You will be fine with those measurements also dont forget to include your port volume which is around 0.00773 cu.ft. Also i thought to let you know that the box will actually be tuned fairly high with these measurements around 48-50 hz. So perhaps you should consider lengthening your port to about 7 inches long and youre width to 22 inches. This will bring youre tuning down to 37-38hz. And always when building you should allow for your speaker displacement also which will affect youre internal volume and tuning.

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L0W T0N3Z AUDIO

NORTHERN AUTO SOUND