anyone ever built a dual opposing woofer box?

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ttocs
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anyone ever built a dual opposing woofer box?

Post by ttocs »

I have finally located my 2nd subwoofer and its got me dreaming of the box for it. I have been considering building a box just behind the back seat where one woofer would face into the cabin area, the other to the trunk. Would cancellation be a problem?
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lilviper
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Re: anyone ever built a dual opposing woofer box?

Post by lilviper »

Are you going isobaric with the idea?

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ttocs
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Re: anyone ever built a dual opposing woofer box?

Post by ttocs »

no, it would be a regular box just with woofers facing away from each other.
what else can I say I am a grumpy asshole most of the time.
lilviper
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Re: anyone ever built a dual opposing woofer box?

Post by lilviper »

180 degrees out?

You could wire them out of phase to eliminate cancellation

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ttocs
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Re: anyone ever built a dual opposing woofer box?

Post by ttocs »

Correct me if I am wrong but I know from experience that would make for nearly perfect cancellation if both woofers were to be mounted regular and wired out of phase in a standard box(which is all this is). For every inch one went out, one would go in the same amount. Again its just a standard box but one woofer would face forward into the cabin area and the other back to the trunk. I know I have seen systems with one woofer on one side of the trunk and the other across facing it and it still slammed and the old rule of where the subs are does not matter since the bass goes in every direction anyway but like I said never seen a box like I describe. I have considered mounting one woofer inverted just for looks really and if I did that I would wire it inverted but I have not made my mind up on that yet.
what else can I say I am a grumpy asshole most of the time.
lilviper
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Re: anyone ever built a dual opposing woofer box?

Post by lilviper »

Good point. You could always build it and wire it both ways, if one is firing into the box and one is firing out, the only difference in phase is the physical difference in distance between the subs eminating the two waves. Which shouldnt be noticeable at that close of a distance.


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Mr. Wild
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Re: anyone ever built a dual opposing woofer box?

Post by Mr. Wild »

If your car is a sedan then I would not consider this arrangement. The subs would be radiating into two different environments and this could cause all sorts of problems.
If your car is a station wagon or hatchback where the trunk and cabin are essentially the same airspace then why not.

Wiring the subs out of phase would make it a compound dipole sub with a redundant box and only half the effective driver radiating area. So don't do that. Utter waste of drivers and space.

I would put both drivers either on the trunk side or rear seat side unless there is some force majeur situation.
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ttocs
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Re: anyone ever built a dual opposing woofer box?

Post by ttocs »

the trunk is not sealed off from the cabin. I had thought about this and agree that if it were there would be differences but with no back seat, its basically a hatch back. Wiring the subs out of phase was never an option as I have seen boxes that have done this on accident and it doesn't cut the sound in half, it completely cancels it. After a lot of thought I have seen countless systems with on sub on one side of the trunk and another on the other side directly facing it and they never had a problem.
what else can I say I am a grumpy asshole most of the time.
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JK
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Re: anyone ever built a dual opposing woofer box?

Post by JK »

That’s how my roadster kinda is.. 2 subs on the left side facing the right side.. 2 subs on the right side facing the left side.. I have 2 separate boxes in the trunk though.. in each box one speaker faces in and the other faces out.. it a highboy with no roof, so I’m only going to get so much sound.. it’s more for show, but the 4 first gen solo’s sounds pretty good back there.. I’m not sure if your wanting to do 2 boxes or one.. you could always do a dual bandpass box with the rectangle port LOL!!, but 2 subs in a sealed enclosure banging off the rear always works well..
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