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4th order blow-through build help, 6 18's


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What's up guys? I bought a 99 ford f-350 powerstroke long bed dually over the weekend and I am ready to get my install going. I have never built a 4th order before so any help is appreciated. The equipment will be (6) obsidian audio 18's running on a crecendo 3500 for now. The subs will be in the bed of the truck with the port in the back window. Basically like John Hone's truck build.

What I am planning now is having the subs firing up. Would there be any issues with this as opposed to firing forward? Also, What ratio would you recommend since I have all the airspace I need. With the tuning, I was thinking around 48 hz but I really want to be able to hit the low lows so I'm not sure what would be ideal.

One last question, with the 4th orders, what is the ideal port area per sq ft? would 16 in be fine?

Like I said, any help is appreciated as this is my first bandpass. And I will for sure post build logs! :drink40:

Edit: Forgot to mention, There will be a camper shell that is sealed of course.

Audio Build

Ride: 2002 Chevy Blazer 4 door

Head Unit: Pioneer deh-80prs

Subs: 4 DC Level 3 15's in a 4th order wall designed by Trent Choate and Jeff Smith

Subs Amp: AQ 3500.1 at wired at .5 (soon to be 2)

Mids/Highs Amp: Skar 85.4

Mids/Highs: Skar components

Electrical: Mechman 270 amp alt, 2 runs of Knu 0 gauge, XS Power d3400, 2 Deka Group 9a31

Build log : http://www.stevemeadedesigns.com/board/topic/167658-indianabasshead-blazer-dc-audio-4th-order-wall-build/


Perfomance Build

2003 Nissan 350z

Greddy Twin Turbo, 3" Test pipes with Borla high-flow cats, Crawford Performance Plenum, Greddy E-manage Ultimate ECU

Exedy Racing Clutch, Built Motor by Racing Innovations

Greddy Over-fender aero kit (1 of 20 ever made), 19" Racing Hart r5 pro wheels
466rwhp


Bike

2008 Midnight Blue Kawasaki ZX-14

Stretched 8" and lowered, Brocks Sidewinder exhaust, Power Commander 5

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What's up guys? I bought a 99 ford f-350 powerstroke long bed dually over the weekend and I am ready to get my install going. I have never built a 4th order before so any help is appreciated. The equipment will be (6) obsidian audio 18's running on a crecendo 3500 for now. The subs will be in the bed of the truck with the port in the back window. Basically like John Hone's truck build.

What I am planning now is having the subs firing up. Would there be any issues with this as opposed to firing forward? Also, What ratio would you recommend since I have all the airspace I need. With the tuning, I was thinking around 48 hz but I really want to be able to hit the low lows so I'm not sure what would be ideal.

One last question, with the 4th orders, what is the ideal port area per sq ft? would 16 in be fine?

Like I said, any help is appreciated as this is my first bandpass. And I will for sure post build logs! :drink40:

Edit: Forgot to mention, There will be a camper shell that is sealed of course.

Demo when done, first!

1998 Pontiac grand prix gtp supercharged2 12" Obsidain Audio V.1 on a 2011 zx1500.1 at 2 ohms. 20ft of Knuconceptz CCA 0 Guage. 2nd Battery is a Shurken BT-120. Box is 3.5cu tuned at 31.8hz sealed off from the trunk. 14sqft of Dynamat on the Rear deck top & bottom. Soon to be more for doors/roof. Gets low & loud

Did a 140.5 Sealed at Battle of the boom in June 2013 dropping to 12.7v (need a alt mines going bad)

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What's up guys? I bought a 99 ford f-350 powerstroke long bed dually over the weekend and I am ready to get my install going. I have never built a 4th order before so any help is appreciated. The equipment will be (6) obsidian audio 18's running on a crecendo 3500 for now. The subs will be in the bed of the truck with the port in the back window. Basically like John Hone's truck build.

What I am planning now is having the subs firing up. Would there be any issues with this as opposed to firing forward? Also, What ratio would you recommend since I have all the airspace I need. With the tuning, I was thinking around 48 hz but I really want to be able to hit the low lows so I'm not sure what would be ideal.

One last question, with the 4th orders, what is the ideal port area per sq ft? would 16 in be fine?

Like I said, any help is appreciated as this is my first bandpass. And I will for sure post build logs! :drink40:

Edit: Forgot to mention, There will be a camper shell that is sealed of course.

Demo when done, first!

for sure if you come to Indiana lol. but does anyone have any input to give me?

Audio Build

Ride: 2002 Chevy Blazer 4 door

Head Unit: Pioneer deh-80prs

Subs: 4 DC Level 3 15's in a 4th order wall designed by Trent Choate and Jeff Smith

Subs Amp: AQ 3500.1 at wired at .5 (soon to be 2)

Mids/Highs Amp: Skar 85.4

Mids/Highs: Skar components

Electrical: Mechman 270 amp alt, 2 runs of Knu 0 gauge, XS Power d3400, 2 Deka Group 9a31

Build log : http://www.stevemeadedesigns.com/board/topic/167658-indianabasshead-blazer-dc-audio-4th-order-wall-build/


Perfomance Build

2003 Nissan 350z

Greddy Twin Turbo, 3" Test pipes with Borla high-flow cats, Crawford Performance Plenum, Greddy E-manage Ultimate ECU

Exedy Racing Clutch, Built Motor by Racing Innovations

Greddy Over-fender aero kit (1 of 20 ever made), 19" Racing Hart r5 pro wheels
466rwhp


Bike

2008 Midnight Blue Kawasaki ZX-14

Stretched 8" and lowered, Brocks Sidewinder exhaust, Power Commander 5

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Oh thought you lived in nj.

& I'm not 100%, with 4ths so ill be quiet & wait for the build log

1998 Pontiac grand prix gtp supercharged2 12" Obsidain Audio V.1 on a 2011 zx1500.1 at 2 ohms. 20ft of Knuconceptz CCA 0 Guage. 2nd Battery is a Shurken BT-120. Box is 3.5cu tuned at 31.8hz sealed off from the trunk. 14sqft of Dynamat on the Rear deck top & bottom. Soon to be more for doors/roof. Gets low & loud

Did a 140.5 Sealed at Battle of the boom in June 2013 dropping to 12.7v (need a alt mines going bad)

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there wouldn't be any issues firing them up, just make sure you can get enough height to get a good ratio. a minimum 1:2 ratio. double up on wood all the way around, make the port removable so you can play with tuning and port area. port area isn't related to volume. shoot for about 880 sq inches of port, then you can adjust port area and tuning from there.

i'm coming up with numbers of about 24 cubes sealed net, and for a 1:2 ratio, 48 cubes ported net.

hope you have the space for this haha. this thing is gonna be huge.

also, PM me once you get some numbers for this. I'd be glad to sketch it up for you :)

Just say no to Ground Pounder Customs.

More box builds

some cars do over 170db with one sub, so clearly my two 12"s can do that in my car, with my knowledge too! look out bitches!

I'm with captain stupid.

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Hey man, I built the truck in the video I am including in your thread. Many people told me not to do subs up with port forward, but it honestly worked out great in this truck. I won't lie one bit about one aspect....the truck falls flat on it's face if the windows are up and doors are shut...only does a 52-53 from 32-47 Hz.....as soon as you roll the windows down though, this thing instantly jumps to a 56- 57......it's crazy as hell.

All of that being said, I went with right around 2.8 cubes net sealed per woofer and then the ported chamber is right around 22 cubes net with 310 square inches of port. Obviously this is not the biggest ratio, but it worked out great for this truck. With 4th order alignments, it's safe to say most folks go with a 2:1 ratio (ported to sealed). It would also be my suggestion to stay somewhere between 14-18 square inches of port per ported cube and a tuning of 46-51 Hz. The best advice anyone can give you on the ported chamber is to start with the largest port possible and then start testing/shrinking/testing/shrinking from there until you begin to lose Db's.

I would also encourage you to read through this thread on CACO for further information. The thread is super long, but there's lots of great information in there about 4th order alignments.

http://www.caraudioclassifieds.org/forum/general-car-audio-discussion-questions/123066-4th-orders-why-some-people-so-quiet-them.html

1999 2 Door Chevy Tahoe 5.7L V8

K&N Cold Air Intake

Kenwood KDC-BT555U

1 Clarion EQS746 Equalizer

1 Clarion MCD360 Crossover

4 Incriminator Audio 1st Gen Warden 18's - 4th Order Bandpass Wall

4 Incriminator Audio 40.1s

8 PRV Audio 8MB450 8" Mid-Range Drivers

8 PRV Audio 6MB200 6" Mid-Range Drivers

1 Stetsom 3K3ES

8 PRV Audio TW350Ti Titanium Bullet Super Tweeter

1 NVX JAD800.4

2 XS Power XP2000s

8 XS Power XP3000s

10 sets of Team Project DB BA60 Battery Terminals

3 Mechman 270 amp alternators

GETTIN LOUDER DAILY!

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there wouldn't be any issues firing them up, just make sure you can get enough height to get a good ratio. a minimum 1:2 ratio. double up on wood all the way around, make the port removable so you can play with tuning and port area. port area isn't related to volume. shoot for about 880 sq inches of port, then you can adjust port area and tuning from there.

i'm coming up with numbers of about 24 cubes sealed net, and for a 1:2 ratio, 48 cubes ported net.

hope you have the space for this haha. this thing is gonna be huge.

also, PM me once you get some numbers for this. I'd be glad to sketch it up for you :)

thanks for the help! I appreciate it. I will take some measurements tonight after i get off work. That thing will probably fill up the whole truck bed!! But I will pm you once I come up with measurements and we can go from there. May have to switch to 15's. But I get off work at 11 pm est and I'll measure then.

Hey man, I built the truck in the video I am including in your thread. Many people told me not to do subs up with port forward, but it honestly worked out great in this truck. I won't lie one bit about one aspect....the truck falls flat on it's face if the windows are up and doors are shut...only does a 52-53 from 32-47 Hz.....as soon as you roll the windows down though, this thing instantly jumps to a 56- 57......it's crazy as hell.

All of that being said, I went with right around 2.8 cubes net sealed per woofer and then the ported chamber is right around 22 cubes net with 310 square inches of port. Obviously this is not the biggest ratio, but it worked out great for this truck. With 4th order alignments, it's safe to say most folks go with a 2:1 ratio (ported to sealed). It would also be my suggestion to stay somewhere between 14-18 square inches of port per ported cube and a tuning of 46-51 Hz. The best advice anyone can give you on the ported chamber is to start with the largest port possible and then start testing/shrinking/testing/shrinking from there until you begin to lose Db's.

I would also encourage you to read through this thread on CACO for further information. The thread is super long, but there's lots of great information in there about 4th order alignments.

http://www.caraudioc...quiet-them.html

alright, i will check out that thread. Thanks for the help! I can't view videos while I'm at work but I will check it out tonight. I'll post updates tonight with measurement specs.

Audio Build

Ride: 2002 Chevy Blazer 4 door

Head Unit: Pioneer deh-80prs

Subs: 4 DC Level 3 15's in a 4th order wall designed by Trent Choate and Jeff Smith

Subs Amp: AQ 3500.1 at wired at .5 (soon to be 2)

Mids/Highs Amp: Skar 85.4

Mids/Highs: Skar components

Electrical: Mechman 270 amp alt, 2 runs of Knu 0 gauge, XS Power d3400, 2 Deka Group 9a31

Build log : http://www.stevemeadedesigns.com/board/topic/167658-indianabasshead-blazer-dc-audio-4th-order-wall-build/


Perfomance Build

2003 Nissan 350z

Greddy Twin Turbo, 3" Test pipes with Borla high-flow cats, Crawford Performance Plenum, Greddy E-manage Ultimate ECU

Exedy Racing Clutch, Built Motor by Racing Innovations

Greddy Over-fender aero kit (1 of 20 ever made), 19" Racing Hart r5 pro wheels
466rwhp


Bike

2008 Midnight Blue Kawasaki ZX-14

Stretched 8" and lowered, Brocks Sidewinder exhaust, Power Commander 5

Link to comment
Share on other sites

Hey man, I built the truck in the video I am including in your thread. Many people told me not to do subs up with port forward, but it honestly worked out great in this truck. I won't lie one bit about one aspect....the truck falls flat on it's face if the windows are up and doors are shut...only does a 52-53 from 32-47 Hz.....as soon as you roll the windows down though, this thing instantly jumps to a 56- 57......it's crazy as hell.

All of that being said, I went with right around 2.8 cubes net sealed per woofer and then the ported chamber is right around 22 cubes net with 310 square inches of port. Obviously this is not the biggest ratio, but it worked out great for this truck. With 4th order alignments, it's safe to say most folks go with a 2:1 ratio (ported to sealed). It would also be my suggestion to stay somewhere between 14-18 square inches of port per ported cube and a tuning of 46-51 Hz. The best advice anyone can give you on the ported chamber is to start with the largest port possible and then start testing/shrinking/testing/shrinking from there until you begin to lose Db's.

I would also encourage you to read through this thread on CACO for further information. The thread is super long, but there's lots of great information in there about 4th order alignments.

http://www.caraudioc...quiet-them.html

Was looking at that thread and another question came up.. Do you think I would be just as loud if not louder doing 4 OA 18's with a 3:1 ratio instead of 6 with a 2:1? If so, that would be a lot easier to build and would save me a little cash.

Audio Build

Ride: 2002 Chevy Blazer 4 door

Head Unit: Pioneer deh-80prs

Subs: 4 DC Level 3 15's in a 4th order wall designed by Trent Choate and Jeff Smith

Subs Amp: AQ 3500.1 at wired at .5 (soon to be 2)

Mids/Highs Amp: Skar 85.4

Mids/Highs: Skar components

Electrical: Mechman 270 amp alt, 2 runs of Knu 0 gauge, XS Power d3400, 2 Deka Group 9a31

Build log : http://www.stevemeadedesigns.com/board/topic/167658-indianabasshead-blazer-dc-audio-4th-order-wall-build/


Perfomance Build

2003 Nissan 350z

Greddy Twin Turbo, 3" Test pipes with Borla high-flow cats, Crawford Performance Plenum, Greddy E-manage Ultimate ECU

Exedy Racing Clutch, Built Motor by Racing Innovations

Greddy Over-fender aero kit (1 of 20 ever made), 19" Racing Hart r5 pro wheels
466rwhp


Bike

2008 Midnight Blue Kawasaki ZX-14

Stretched 8" and lowered, Brocks Sidewinder exhaust, Power Commander 5

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If you can get a 3:1 ratio, then potentially. Could give you a more definitive answer with dimensions.

4 18's - 3:1 ratio 16 cubes sealed 48 ported

6 18's - 2:1 ratio 24 cubes sealed 48 ported

6 15's - 2:1 ratio 15 cubes sealed 30 ported

6 15's - 3:1 ratio 15 cubes sealed 45 ported

these are just arbitrary numbers. depending on how much power you plan on giving the woofers down the road, these numbers may get smaller or bigger.

Just say no to Ground Pounder Customs.

More box builds

some cars do over 170db with one sub, so clearly my two 12"s can do that in my car, with my knowledge too! look out bitches!

I'm with captain stupid.

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6 18's in a 4th is huge lol im not sure what you mean by the box design. Do you have any pics to help me understand and if you want lows tunning will play a part so id say lowest tunning to go for is 44hz but its mostly in the sealed chamber. Make a bigger sealed chamber and you have to go with a 2:1 minimum you can go less if needed. The higher the ratio the more spl and less bandwidth

Johns.jpgSuburban Coming Soon

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