I have been reading all kind of forms and advice on ported boxes and i have a few questions. Once i know the cubic feet i have and i wanna tune my box to 40 htz do i have to add the port size to my total cubic feet or is it subtracted from it?
Replies (18)
jrose2002 on 06/17/2008 18:13:09
Ford Expedition 2000, maxxsonic xxv 2x, 4 DDz 18's (Digital Designs), and there will be many other bells and whistles.
newB on 06/17/2008 18:21:01
your looking at some top of the line professional equipment right there. The basic answer is yes- you treat the port as a solid object and add the volume to the total volume. But if your running DDz and some XXVs i would recommend having a pro build it. All that money could go to waste real quick in a bad box.
-drew
swez on 06/17/2008 23:23:41
If you don't have the tools and skills to build such an enclosure, hire a Pro that knows these subs well and can build the right box for them to fit in your ride.
Also, since these are 18" subs, consider dropping your port tuning target to say 32 Hz. That means a larger box, larger slotted ports and more breathing space for these subs. A variable Infrasonic/subsonic filter is a must in this package. (Set to ~25-30 Hz.)
Fortunately, you have a larger SUV truck. The cargo space is adequate and cabin gain effects will help considerably. As Drew mentioned, great subs and a strong amp in the wrong box will not satisfy the bass you crave. (Back to the drawing board)
If you run into a guy that does not recommend firing the subs toward the rear doorsbumper, find another guy.
Swez
Ash on 06/18/2008 08:06:57
This is all of course without the 3rd row seat, right? I've done an install in an Expedition once and it's unbelievable how little room is back there. I barely had enough room to squeeze 2 memphis 12" requiring about 1.25ft^3 each and still have decent line of sight out of the rear window.
With a pair of 18", you definitely will have to sacrifice some seating.
UKinstaller on 06/18/2008 08:09:22
yeah that box is gonna require pulling out the third row, middle, and front seats!
-UK
newB on 06/18/2008 09:46:20
how do you drive without front seats??
sounds like your doing a wall behind the A pillar (which i do approve of) BUT make sure you find a builder that knows what he/she is doing.
Swez-
In large SUVs with Multiple 18s and the box under the window line I've seen best results from woofer up with ports back. Any particular gain to woofers+port back?
-Drew
swez on 06/18/2008 12:52:34
If the vehicle has a tall roof, (like in many PU.SUV installs) upfiring works very well. There's plenty of air space for bass to propagate in that space. If fills the whole cabin well when it's done right.
In a vented system, the ports do most of the heavy, low bass near PTF. (Port Tuning Freq) It makes perfect sense to fire the ports back to the rear and subs fire upward. The upper bass is directly radiating while the ports get the greater benefit of cabin gain below about 55 Hz. It really depends on the natural resonance of the cabin. That's where the cabin gain factor really comes into play.
Am not a "Basshead" by any means. So, I would defer to experts who have been in that game and know the tricks of the trade and how to squeeze ever dB of SPL out of their systems. (Like Steve Meade)
Swez
jrose2002 on 06/18/2008 17:03:47
I'm using the entire back space 3rd row out which would be close to 40*48*35=67200/1728=38.88 cf so i have 39 total feet to work with not counting enclosure space. I wont be able to look out of the rear cabin but i can use the rear view camera. i would like to build a box that has some type of style but i would really like to get great spl aleast enough to win some of my money back at some of these small sound offs.
I will be doing the building im a Drillng rig mechanic by day and a remodeler (new home contractor) in the afternoon and weekends.
I already have the amps havent dropped the money to get the subs yet so im open to any advice cause this is bout to drive me crazy lol
Victor on 06/18/2008 21:13:59
WALL
would be the best approach here....
also i am sure you have considered upgrading the alternator, and get a couple of Deep cycle batts for a stable powersupply...
loads and loads of Damping too....
swez on 06/19/2008 04:55:46
Victor,
Can you give us details and pics/links to "Wall" of subs designs that you have seen and maybe worked on with your crew of fabricators?
I have a good understanding of this concept in Pro-Line/Live music apps, but am not sure how to scale things for a vehicle.
Comments?
Swez
Ash on 06/19/2008 07:09:00
I agree with Vic, build a wall... However, it will take some serious planning and exact measuring to do it. The contours of the cab itself should be the hardest, but that's just for the baffle if done that way.
Show us some pics Vic....
Ash
newB on 06/19/2008 09:36:39
Wall pix or BAN!!!!
GRIN
-Drew
Victor on 06/19/2008 16:59:50
BAN GRINGRINGRIN
i have done only a couple of these, with CV Vmax12 subs, both using 4 subs and 2 amps EXL1200.1 ...both measured a tad bit above 155db..... Never documented them so dont have pics, but can definitely share my experience....
at this moment i am more concerned about your cars electrical's and sound damping before even thinking about the enclosure design.
PS: Regarding working with the contours of any vehicle, one needs a flexible material, wood is out of question, other than the basic framing, base or the support structure, fiberglass is a very good material to work with in such a case..
if ure planning to compete, and win.... get the fundamentals right and u'll be a happy man...
use multiple damping agents -
1st layer would be the damping paint... with this you should insure that every nook and corner of the car is covered... this layer will eliminate the residual vibrations propagating in the sheet metal...
2nd layer would be the damping sheets to add considerable weight to the sheet metal to avoid flexing and check the loss of SPL... these mats should be used at everyplace your hand can reach and the sheet can adhere to...
larger spans of metal without a reinforce structure needs more damping... that calls for an extra layer on the roof, doors, and boot and other places as you see it necessary.
with the electrical's , you would need a 250amp or bigger alt with atleast 2 deep cycle batteries of around 800 - 1000CCA capacity,,,,you will definitely need the big 3 upgrade when you upgrade the alt and batt.... no capacitors would work here....
get the 0/2/4/8 gauge wiring and wiring accessories, like terminals, fuse holders, circuit breakers, distribution blocks etc....before u even buy any more electronic gadgets.
plan everything on paper before you go shopping... every single detail should be put on paper, designs, list of equipments, wiring diagrams etc....
just need to do the homework right.... this sure is some unwanted advice, but it definitely is something you need to pay heed to...
once you are through with all this, and have a base ready, i'll surely help you with diagrams, schematics, dimensions, fiberglass and with the help of others at CK , walk you through the entire process...
please take a lot of pictures of the insides of your car, specially the part where the wall will come up... try to take flat 2d pics, will get easier to trace while doing drawings ......
perspectives and interesting angles do look good in pics, but dont give an exact idea about dimensions and size ratios....
jrose2002 on 06/20/2008 19:21:11
thanks Victor this is all wanted advice ive never competed just always have the best system in the neighborhood, and i think its time to move up.
I take all of this and do some homework and when i get it all figured out ill post what i decided to do.
Which two sound dampening materials do you recommend?
Victor on 06/20/2008 20:21:20
http://www.clubknowledge.com/cgi-bin/car_audio_faq/faq.cgi?g4137
http://www.clubknowledge.com/cgi-bin/car_audio_faq/faq.cgi?g3764
check these links...
PS: e-designs have a good product line, branded e-dead they will give you some very good deal, on an entire package...
Paint , Mat and Teklite ( high freq absorbtion mat )
a layer of each will insure an almost close to inert environment for sound in your car...
Paint : http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=53
and paint brush
http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=101
Mat : http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=52
Roller : to install the mat properly
http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=100
Teklite : Neoprene high freq absorbant rubber sheet
http://www.edesignaudio.com/product_info.php?t=0&products_id=55
---------------------------------------------------------------------------------------
ask them for a special pricing on the entire package and they'll give you a good deal.
you'll need 1 gallon of paint, 100 sq.ft of mat and 25 sq.ft of teklite ( they 'll ask you to buy a 100sq.ft of teklite and suggest you to use it as a layer above the sound damping mat through out your car... it would be nice to do so, but i do not see it necessary, use it only at required places.......using teklite on just the 4 door panels will suffice.... and bits here and there where u see it necessary... i have found this effective if used on reverse side of removable plastic parts inside the cabin...)
hope that helps..
Victor..
you can look at other products and manufacturers too. i suggested edesigns cause they provide quality products and very competitive rates and are a growing community too.. price/performance ratio of all e-dead products is real good...
Victor on 06/24/2008 16:27:26
keep us posted with developments on this project...
jrose2002 on 06/24/2008 17:25:07
I will and i have another question for you about my power system.
Victor on 06/24/2008 20:05:39
and ... what is that???
Replies (18)
jrose2002 on 06/17/2008 18:13:09
Ford Expedition 2000, maxxsonic xxv 2x, 4 DDz 18's (Digital Designs), and there will be many other bells and whistles.
newB on 06/17/2008 18:21:01
your looking at some top of the line professional equipment right there. The basic answer is yes- you treat the port as a solid object and add the volume to the total volume. But if your running DDz and some XXVs i would recommend having a pro build it. All that money could go to waste real quick in a bad box.
-drew
swez on 06/17/2008 23:23:41
If you don't have the tools and skills to build such an enclosure, hire a Pro that knows these subs well and can build the right box for them to fit in your ride.
Also, since these are 18" subs, consider dropping your port tuning target to say 32 Hz. That means a larger box, larger slotted ports and more breathing space for these subs. A variable Infrasonic/subsonic filter is a must in this package. (Set to ~25-30 Hz.)
Fortunately, you have a larger SUV truck. The cargo space is adequate and cabin gain effects will help considerably. As Drew mentioned, great subs and a strong amp in the wrong box will not satisfy the bass you crave. (Back to the drawing board)
If you run into a guy that does not recommend firing the subs toward the rear doorsbumper, find another guy.
Swez
Ash on 06/18/2008 08:06:57
This is all of course without the 3rd row seat, right? I've done an install in an Expedition once and it's unbelievable how little room is back there. I barely had enough room to squeeze 2 memphis 12" requiring about 1.25ft^3 each and still have decent line of sight out of the rear window.
With a pair of 18", you definitely will have to sacrifice some seating.
UKinstaller on 06/18/2008 08:09:22
yeah that box is gonna require pulling out the third row, middle, and front seats!
-UK
newB on 06/18/2008 09:46:20
how do you drive without front seats??
sounds like your doing a wall behind the A pillar (which i do approve of) BUT make sure you find a builder that knows what he/she is doing.
Swez-
In large SUVs with Multiple 18s and the box under the window line I've seen best results from woofer up with ports back. Any particular gain to woofers+port back?
-Drew
swez on 06/18/2008 12:52:34
If the vehicle has a tall roof, (like in many PU.SUV installs) upfiring works very well. There's plenty of air space for bass to propagate in that space. If fills the whole cabin well when it's done right.
In a vented system, the ports do most of the heavy, low bass near PTF. (Port Tuning Freq) It makes perfect sense to fire the ports back to the rear and subs fire upward. The upper bass is directly radiating while the ports get the greater benefit of cabin gain below about 55 Hz. It really depends on the natural resonance of the cabin. That's where the cabin gain factor really comes into play.
Am not a "Basshead" by any means. So, I would defer to experts who have been in that game and know the tricks of the trade and how to squeeze ever dB of SPL out of their systems. (Like Steve Meade)
Swez
jrose2002 on 06/18/2008 17:03:47
I'm using the entire back space 3rd row out which would be close to 40*48*35=67200/1728=38.88 cf so i have 39 total feet to work with not counting enclosure space. I wont be able to look out of the rear cabin but i can use the rear view camera. i would like to build a box that has some type of style but i would really like to get great spl aleast enough to win some of my money back at some of these small sound offs.
I will be doing the building im a Drillng rig mechanic by day and a remodeler (new home contractor) in the afternoon and weekends.
I already have the amps havent dropped the money to get the subs yet so im open to any advice cause this is bout to drive me crazy lol
Victor on 06/18/2008 21:13:59
WALL
would be the best approach here....
also i am sure you have considered upgrading the alternator, and get a couple of Deep cycle batts for a stable powersupply...
loads and loads of Damping too....
swez on 06/19/2008 04:55:46
Victor,
Can you give us details and pics/links to "Wall" of subs designs that you have seen and maybe worked on with your crew of fabricators?
I have a good understanding of this concept in Pro-Line/Live music apps, but am not sure how to scale things for a vehicle.
Comments?
Swez
Ash on 06/19/2008 07:09:00
I agree with Vic, build a wall... However, it will take some serious planning and exact measuring to do it. The contours of the cab itself should be the hardest, but that's just for the baffle if done that way.
Show us some pics Vic....
Ash
newB on 06/19/2008 09:36:39
Wall pix or BAN!!!!
GRIN
-Drew
Victor on 06/19/2008 16:59:50
BAN GRINGRINGRIN
i have done only a couple of these, with CV Vmax12 subs, both using 4 subs and 2 amps EXL1200.1 ...both measured a tad bit above 155db..... Never documented them so dont have pics, but can definitely share my experience....
at this moment i am more concerned about your cars electrical's and sound damping before even thinking about the enclosure design.
PS: Regarding working with the contours of any vehicle, one needs a flexible material, wood is out of question, other than the basic framing, base or the support structure, fiberglass is a very good material to work with in such a case..
if ure planning to compete, and win.... get the fundamentals right and u'll be a happy man...
use multiple damping agents -
1st layer would be the damping paint... with this you should insure that every nook and corner of the car is covered... this layer will eliminate the residual vibrations propagating in the sheet metal...
2nd layer would be the damping sheets to add considerable weight to the sheet metal to avoid flexing and check the loss of SPL... these mats should be used at everyplace your hand can reach and the sheet can adhere to...
larger spans of metal without a reinforce structure needs more damping... that calls for an extra layer on the roof, doors, and boot and other places as you see it necessary.
with the electrical's , you would need a 250amp or bigger alt with atleast 2 deep cycle batteries of around 800 - 1000CCA capacity,,,,you will definitely need the big 3 upgrade when you upgrade the alt and batt.... no capacitors would work here....
get the 0/2/4/8 gauge wiring and wiring accessories, like terminals, fuse holders, circuit breakers, distribution blocks etc....before u even buy any more electronic gadgets.
plan everything on paper before you go shopping... every single detail should be put on paper, designs, list of equipments, wiring diagrams etc....
just need to do the homework right.... this sure is some unwanted advice, but it definitely is something you need to pay heed to...
once you are through with all this, and have a base ready, i'll surely help you with diagrams, schematics, dimensions, fiberglass and with the help of others at CK , walk you through the entire process...
please take a lot of pictures of the insides of your car, specially the part where the wall will come up... try to take flat 2d pics, will get easier to trace while doing drawings ......
perspectives and interesting angles do look good in pics, but dont give an exact idea about dimensions and size ratios....
jrose2002 on 06/20/2008 19:21:11
thanks Victor this is all wanted advice ive never competed just always have the best system in the neighborhood, and i think its time to move up.
I take all of this and do some homework and when i get it all figured out ill post what i decided to do.
Which two sound dampening materials do you recommend?
Victor on 06/20/2008 20:21:20
http://www.clubknowledge.com/cgi-bin/car_audio_faq/faq.cgi?g4137
http://www.clubknowledge.com/cgi-bin/car_audio_faq/faq.cgi?g3764
check these links...
PS: e-designs have a good product line, branded e-dead they will give you some very good deal, on an entire package...
Paint , Mat and Teklite ( high freq absorbtion mat )
a layer of each will insure an almost close to inert environment for sound in your car...
Paint : http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=53
and paint brush
http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=101
Mat : http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=52
Roller : to install the mat properly
http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=100
Teklite : Neoprene high freq absorbant rubber sheet
http://www.edesignaudio.com/product_info.php?t=0&products_id=55
---------------------------------------------------------------------------------------
ask them for a special pricing on the entire package and they'll give you a good deal.
you'll need 1 gallon of paint, 100 sq.ft of mat and 25 sq.ft of teklite ( they 'll ask you to buy a 100sq.ft of teklite and suggest you to use it as a layer above the sound damping mat through out your car... it would be nice to do so, but i do not see it necessary, use it only at required places.......using teklite on just the 4 door panels will suffice.... and bits here and there where u see it necessary... i have found this effective if used on reverse side of removable plastic parts inside the cabin...)
hope that helps..
Victor..
you can look at other products and manufacturers too. i suggested edesigns cause they provide quality products and very competitive rates and are a growing community too.. price/performance ratio of all e-dead products is real good...
Victor on 06/24/2008 16:27:26
keep us posted with developments on this project...
jrose2002 on 06/24/2008 17:25:07
I will and i have another question for you about my power system.
Victor on 06/24/2008 20:05:39
and ... what is that???
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