Wanting info about porting a sealed sub box.
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From: Independence Mo
Car: 89 RS
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Wanting info about porting a sealed sub box.
I just got a sealed sub box for my new 10" polk momo subs. I will be putting 500 watts @ 2 ohms that the two will share from my new alpine class d mono block amp. The sub box is the kind that is fitted for the rear hole in the hatch area. I would love to port the box for deeper bass. Any help on picking the right size port? Whats the formula to figure it out? Not expecting my box to be the same as lots of others. In order for this to be correct then the ports have to be tuned ( by diameter & length) in order to get the sound I am looking for that will work the best with the subs, & amp. Help please only if you know what your talking about. Anyone can take a drill, & jig saw to a box to make some holes. I did it years back. Used some plastic cups that I cut the bottom out of, from my parents kitchen. Not looking for that lol.
the last sub i ported I used a 4" round pvc pipe, ran it as far back in the box as i could then 90'ed it to the top 1" before it hit the wood on the top of the box. Thats what im looking for. Some one that knows that stuff.
the last sub i ported I used a 4" round pvc pipe, ran it as far back in the box as i could then 90'ed it to the top 1" before it hit the wood on the top of the box. Thats what im looking for. Some one that knows that stuff.
Last edited by STRIKER911; Mar 29, 2009 at 02:09 PM.
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Re: Wanting info about porting a sealed sub box.
first off you need to know what ur doing with the subs spl or just deeper base.
2nd you need to know how big of a box you need 4 the sub if its ported usualy ported boxes are 1.5 - 2 X bigger depending on application
what hz do u want the box to be tuned 2 ?
what is the cubic feet of airspace in the box ur working with?
2nd you need to know how big of a box you need 4 the sub if its ported usualy ported boxes are 1.5 - 2 X bigger depending on application
what hz do u want the box to be tuned 2 ?
what is the cubic feet of airspace in the box ur working with?
Thread Starter
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iTrader: (1)
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From: Independence Mo
Car: 89 RS
Engine: 305 TBI (lo3)
Transmission: 700r4
Axle/Gears: Whatever is stock.
Re: Wanting info about porting a sealed sub box.
first off you need to know what ur doing with the subs spl or just deeper base.
2nd you need to know how big of a box you need 4 the sub if its ported usualy ported boxes are 1.5 - 2 X bigger depending on application
what hz do u want the box to be tuned 2 ?
what is the cubic feet of airspace in the box ur working with?
2nd you need to know how big of a box you need 4 the sub if its ported usualy ported boxes are 1.5 - 2 X bigger depending on application
what hz do u want the box to be tuned 2 ?
what is the cubic feet of airspace in the box ur working with?
Re: Wanting info about porting a sealed sub box.
Post a picture of your box, 2.16 per side or 4.32 cubic feet is a lot of airspace for a box that fits in the well of a F-Body, and that's not even including material thickness.
Usually those boxes are less than a few cubic feet total. Are you sure yours isn't 2.16 cubic feet total?
Usually those boxes are less than a few cubic feet total. Are you sure yours isn't 2.16 cubic feet total?
Thread Starter
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From: Independence Mo
Car: 89 RS
Engine: 305 TBI (lo3)
Transmission: 700r4
Axle/Gears: Whatever is stock.
Re: Wanting info about porting a sealed sub box.
Post a picture of your box, 2.16 per side or 4.32 cubic feet is a lot of airspace for a box that fits in the well of a F-Body, and that's not even including material thickness.
Usually those boxes are less than a few cubic feet total. Are you sure yours isn't 2.16 cubic feet total?
Usually those boxes are less than a few cubic feet total. Are you sure yours isn't 2.16 cubic feet total?
Re: Wanting info about porting a sealed sub box.
That's correct, it's inside L x W x H / 1728 to get your cubic feet
Does it look anything like this box made by audio enhancers? It's a total of 1.79 total cubic feet.
Does it look anything like this box made by audio enhancers? It's a total of 1.79 total cubic feet.
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From: Independence Mo
Car: 89 RS
Engine: 305 TBI (lo3)
Transmission: 700r4
Axle/Gears: Whatever is stock.
Re: Wanting info about porting a sealed sub box.
k so you take the three x's them, then divide them by 1728? I didnt divide. Got 1.25 cubic feet when I divided x 1728. The box does look like that one.
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Re: Wanting info about porting a sealed sub box.
ok, 1.25 sounds a little closer to what you have. The bad thing is that it's going to be extremely hard to port a box that size and still sound good. I'm a little partial to sealed enclosures anyways.
If your splitting 1.25 between two 10's that may be a reason why the bass isn't "deep"....the smaller the enclosure the boomier the sound is. 1.25 would be a good sealed (or ported) box for one 10" subwoofer.
I would just throw some poly-fil pillow stuffing in each box, leave it sealed and call it a day. Not much else you can do with it.
Maybe someone else that has another idea can chime in
If your splitting 1.25 between two 10's that may be a reason why the bass isn't "deep"....the smaller the enclosure the boomier the sound is. 1.25 would be a good sealed (or ported) box for one 10" subwoofer.
I would just throw some poly-fil pillow stuffing in each box, leave it sealed and call it a day. Not much else you can do with it.
Maybe someone else that has another idea can chime in
Thread Starter
Senior Member
iTrader: (1)
Joined: Jan 2009
Posts: 562
Likes: 0
From: Independence Mo
Car: 89 RS
Engine: 305 TBI (lo3)
Transmission: 700r4
Axle/Gears: Whatever is stock.
Re: Wanting info about porting a sealed sub box.
ok, 1.25 sounds a little closer to what you have. The bad thing is that it's going to be extremely hard to port a box that size and still sound good. I'm a little partial to sealed enclosures anyways.
If your splitting 1.25 between two 10's that may be a reason why the bass isn't "deep"....the smaller the enclosure the boomier the sound is. 1.25 would be a good sealed (or ported) box for one 10" subwoofer.
I would just throw some poly-fil pillow stuffing in each box, leave it sealed and call it a day. Not much else you can do with it.
Maybe someone else that has another idea can chime in
If your splitting 1.25 between two 10's that may be a reason why the bass isn't "deep"....the smaller the enclosure the boomier the sound is. 1.25 would be a good sealed (or ported) box for one 10" subwoofer.
I would just throw some poly-fil pillow stuffing in each box, leave it sealed and call it a day. Not much else you can do with it.
Maybe someone else that has another idea can chime in

THEN: Prefab box facing the wrong direction loaded with entry audiobahn 12's @ 2 ohms, 200watt mtx amp class d.
NOW: Real Camaro custom box loaded with Polk momo 10's @ 2 ohms, 500 watt alpine amp class d, one farid cap.
Everything was new both times. Wire's where 4 gauge, with moster speaker wire. I bet the new one system will blow the old away. Well I hope, but the lil tens are why I even question it. What do you guys think?
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