imhungnurnot

The final port dimensions are defined very poorly on here. I can figure that out later. Just want to see if this is cool with you..

Ok so here we go. The box will be roughly 1.215 cuft after displacements. The radius of the curve will be 2 inches and will be used for volume. The port will be 2x9.5x34.75 (disregard the 35.25 on the sketch) which will tune the box right at 33Hz with 15.64 square inches of port area per cube of volume. Here are some VERY rough sketches.

What if i fire it into the rear wall? Sorry.. by the time i replied you already answered..

Sub? port? sub and port?

There is already a hole in the metal behind my kick its about 3x4 inches i guess.. but that will be plenty..

Measuring port area isn't shit. You probably just think its more complicated than it really is. When you look at the front of your box, the port is a 2 dimensional rectangle. Right? Well the area of this rectangle (base x height) is your port area for your box. When you talk about port area, you talk about it as a ratio between port area and the net volume of your box. Fi recommends 12-16 square inches of port area per cuft of net volume. Lets say the area of this is 100 square inches and the box is 6 cuft (net volume; meaning after sub and port displacement). You divide the total port area by the net volume of the box (100/6) and you get 16.7 square inches of port per cube of volume. This is a little above the range which isn't a problem except for a long port. Sometimes port area has to be decreased so the port length will be decreased so the box will fit into the space your have in your vehicle. However, if you increase your port area, the port length needed will have to be increased to stay at the same tuning. So lets say i cut down the port area of the box from 100 to 80.. (the port will have to be shortened to keep the same tuning; so it will displace less volume so your subs will have more net volume now) lets say your net volume is now 6.5 cuft. Now 80/6.5 is 12.3 You're still in the range so its good. It's really a number game.. sorry if this is hard to understand.. read it multiple times if necessary..

Up front as in by the windshield? kick? my head? lol I'd like to give it a shot, but I'm trying to do as much planning as I can since 3/4 MDF is 30 bucks a freaking sheet! I remember when I started building (about 4 years ago) 3/4 was like $22.. now the 1/2 is $22..

My original plan was sub up, external port into the passenger side corner so I could switch tuning easily. But I think I'm going to put a battery there. Now I'm leaning toward the idea of porting out of the front with the flares (like in the picture). I'm thinking about firing the sub like the drawing, but maybe decrease the angle so its closer to a downfire setup. But i'll still have an angle on it so the sub will be able to breathe and it may create a horn type affect with the angle.

The vertical part of the box above the sub will be against the back wall. Should I just down fire?

Idk what to tune to for a Home setup. But I have a 4 inch aero port and a Fi X 12 DVC 4 ohm. I was thinking something like 2 cuft tuned around 24 Hz?

When you say you don't think it'll work, is it due to the enclosure size/port/shit im going to calculate? lol or the spare tire issue?

Yes i know.. but in general thinking about a single cab. With my current box, it loads off of the roof which is pretty far away. And it may be harder to compress the air in my cabin because it can easily flow out of my windows. I've heard that utilizing the reflection of sound waves in your vehice (loading) helps with something or other? Not sure if its SQ or SPL. Any thoughts?

It'll definitely work.. I'll punch some numbers tom at work and let you know.

Currently I have a center console in a single cab chevy with sub up and port up. Like so.. Or what about something like thiss?

Don't get me wrong. You're a bad ass builder, but it's basic geometry. Someone would have figured it out anyway. Hell i didn't even calculate anything on mine. Just cut and tested it. If you make more cuts then necessary it doesn't matter because you are going to glue/glass the shit out of it.

That is just a rule of thumb and does not always apply, I actually HATE that little "rule" because the port MUST be designed to suit the woofer, not the enclosure it is in. He's using 7.6 cuft.. he's gonna have a lot of cone area.. he isn't building this for a 6 inch woofer.. more like an 18.. and for high excursion woofers that rule of thumb is necessary. At the very least he'll need to flare the port on both ends Port Area Calc.

Sorry.. I didn't answer that. 1.1 cuft per sub. Remember this is a approximation, but a good one. You told me about 2.6 cuft total.. So I designed it assuming exactly 2.6 cuft total. So you'll probably have a +/- on the tuning of 1 hz at the very greatest. You won't be able to notice this though.. Idk about firing the ports just on one side.. You may get port loading because of the hump in the middle isn't going to allow the air on the passenger side to "see the port" as much as the air on the driver side. i would try to put one on either side of the box firing out of the front.. You can try to put both on the driver side and see how you like it. Or we could get a more experience member on here to help us decide.. Port tuning isn't hard for me now.. The hard part is deciding where to fire sub/port if you have options

Not trying to hate on you.. but those rims have to go.. there's too much going with them.. you need a clean 5 or 6 spoke rim with a nice size lip.. also.. this will be MUCH easier to clean..

DON'T BUILD THAT, YOU'RE BUILDING A DAMN WHISTLE.. LOL THATS ONLY 3.4 SQUARE INCHES OF PORT PER CUBEEE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! How many subs do you have? and what size?

Make it the same on both sides so the box is symmetrical and divide it. You won't loose much airspace, and the divider will be an awesome brace for the top piece. 3" ports are only 7 inches of port area per port.. I did the numbers.. 1.1 cuft per sub. 2 3" (one on each side) 14 inches long.. but its only like 6.5 sqaure inches of port per cube.. 3 inch aeros will be the way to go unless you can flare the 3" pvc. im not too worried about the divider. seem like aero's are what i need with my strict space requirements. so how much net volume will i have with 2 3" aero ports tunned to 33hz? my box is basically done so im stuck with it. haha... I see.. ha. The its basically gonna be the same as with the 3 inch ports , but you add another inch to the port length. Do two 15 inch long ports (from flare to flare; i.e. end to end). You will still only have 6.5 square inches of port per cube. However, you can get away with a 50-75% port area reduction with aero ports because they significantly reduce port air speed. So since 12 square inches per cube is the minimal recommended port area per cube, 54% of this is 6.5 square inches of port area per cube. There you go; you are in the 50-75% range!! This should be a clean sounding setup. You're going to downfire the subs? Port out the front or side?

There is one more piece of information I need. What is the max depth of the of the left side in the top view. (the part where the ports are firing in your drawing) just found out the maximum depth of the box can be 11". So I'm going to scrap my idea And just build a normal box. Is 11" too shallow for a 10" FI BL You're design will work.. why do you want to scrap it? I'm looking for this dimension in this picture..

Yeah, but a trianglular port with a rectangular opening??? Shouldn't matter.. ports are tuned by area and length. So the cross sectional area of the triangle should be equal to the area of the rectangular opening. Do the numbers. Let us know if this is right..

Sounds like something fun to try!

The box is 2.6 cuft @ 39 Hz with 16 square inches of port per cube. Need to build another so I can reach across the truck to roll down the window.. lol (also i think i will tune the next one around 33 hz)

Make it the same on both sides so the box is symmetrical and divide it. You won't loose much airspace, and the divider will be an awesome brace for the top piece. 3" ports are only 7 inches of port area per port.. I did the numbers.. 1.1 cuft per sub. 2 3" (one on each side) 14 inches long.. but its only like 6.5 sqaure inches of port per cube.. 3 inch aeros will be the way to go unless you can flare the 3" pvc.