Advice on 4 nsv3 12s in a 4th order bandpass.

[plexlove]

K guys, designing a build for 4 nsv3 12s and going to be in a 4th order bandpass...but had an idea i wanna run by some of the more experienced builders first.

Ive built several very nice ones but always had the subs on the same wall with motors facing the port.

My idea here (excuse the microsoft paint sketch, i dont have sketchup on this comp) is to have all 4 subs in its own sealed section.

Cant find much info on specs for sealed on the nsv3s but this isnt too technical yet...but guessing round 1.25 each...maybe even 1 cube each.

Itll have around 4k per sub power so 1 cube may work.

Anyway, this is being built for the bed of an avalanche...so what im thinking is do 2 12s one eaxh side of the port in the front...3/4 thick 12"x12" plexiglass window so u can view the two sub up front doin work.

Then in the rear have the other two motors facing port. (all motors will be firing into the ported section.)

Im doing 3:1 ration tuning, mmmm thinking round 45ish maybe tad lower.

I wanna get nasty low but also do numbers...wanna break 60.

So my questions are..

1. Ive never had subs firing in front of the port before let alone front and back. so would you think it would effect anything? As far as soundwaves go, cancelation and what not?

2. Anyone ran or runnin nightshades have any info that might be of use?

I havnt ran the math on any of this yet just designing first.

Thought it would be bad *** to be avle to see the front of the subs on the front two and the motors on the back two...but want to make dang sure it wont decrease output by doing so.

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[plexlove]

It wont let me upload the drsign ssays image too big...anyways guess ill explain clearer then.

Front of enclosure has center port on both sides of it ill have seald boxes with cone firing toward the front, motors facing into ported section.

The front of the enclosure on each side tgat is sealed will be routered out and 3/4" 12x12" plexiglass will be set in for a window to view the front of the two front subs.

The rear will be just like a normal 4th, notors facing ported section....this way you can see two of the cones and two of the motors.

 

[mazdakid 5,000+ posts]

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[germanyt 10+ year member]

Well your drivers can be in just about any direction/configuration you want. As long as they are in phase they'll pressurize the ported chamber just the same. As for the 60 I'd stop getting my hopes up. You won't hit it. And a 24 cube gross enclosure is going to be tough to fit under the tonneau cover with such a small bed. Sounds to me like you have plenty of power. I'd do 4 cubes sealed and 8 ported. You'll still slam and stay linear even with all that power and the lower ratio will keep the response flatter. 3:1 would peak hard and loud but after having just built a 2.5:1 I'd gladly give up 2 db for better response below 30 and above 50.

 

[CSCStang]

well your drivers can be in just about any direction/configuration you want. As long as they are in phase they'll pressurize the ported chamber just the same. As for the 60 i'd stop getting my hopes up. You won't hit it. And a 24 cube gross enclosure is going to be tough to fit under the tonneau cover with such a small bed. Sounds to me like you have plenty of power. I'd do 4 cubes sealed and 8 ported. You'll still slam and stay linear even with all that power and the lower ratio will keep the response flatter. 3:1 would peak hard and loud but after having just built a 2.5:1 i'd gladly give up 2 db for better response below 30 and above 50.

x2

 

[Massive spl]

Make sure you post a build log.... Good. Luck on 4 12s breaking a 160... Not easy my any means

 

[mazdakid 5,000+ posts]

Make sure you post a build log.... Good. Luck on 4 12s breaking a 160... Not easy my any means

Ya that's gonna be fun, wants to play nasty low but break 160 with 4 12s lol

 

[plexlove]

Ok enclosure is **** near finished....ill start taking pics from here on out and post as i go..sorry i didnt reply sooner it never notified me i had replys.

Anyways...what i got after all displacement, bracing, 45's, etc is 16.2 cubes ported side and 1.45 cube sealed per sub making it around 2.75:1 ratio...this box will have zero flex....everything is double layered 3/4 mdf except loading walls are 3 layers....resin between each layer, 2" screws every 2" on all layers...1/4" flat bars running width wise top and bottom with 3/4" all thread going through holding them tight and going through the bed of my truck and bolted to it.

Entire ext is just gonna be resin coated for moisture resistance...all interior corners will be 1 layer matt, 1 layer cloth glassed and and all walls will have 2 layers of cloth glass.....so she will be sturdy! And got very close to the size i wanted.. Tuned to 43hz....i dont really see it being an issue breaking 60 with nightshades on good power.

You guys keep saying 4 12s like they are just run of the mill driver....these are nsv3s...i think they will break 60 fairly easy.

Im debating another alternator though.....currently running 2 300 amp alts...had 2 122ah batts just bought 4 more plus my u der the hood batt...so totalling 839ah worth of batteries....ill be running 2 scv6000's strapped at .5 ohms...never ran these amps so not sure how hungry theyre gonna be...so i may go ahead and buy another alt just to be safe i just didnt wanna go through the hassle of making a triple alt bracket (and sure as hell aint payin hundreds for one i can make for $40 and 2hrs of time)...any thoughts on the power?

Oh and will have 4 runs of pos AND neg from hood batt to battery bank in the rear...aluminum busbar on batts and ordered dual 0 gauge inputs for the amps so will have 8 runs of pos and neg to the amps themselves.

Right now we r getting bad weather so kind had to just toss everything in my truck and call it quits till it ends but after it does my nexts step is running all wiring (just added 3rd layer of dampener to floor) then screwing down 1/8 osb and 1/16 luan to the floor and doing vinyl planks (look like hardwood except waterproof) and new carpet on the floor...googled and have yet to see anyone do a hardwood stule floor board!

After that i gotta finishing some glass work on dash and door panels..do some viynl wrapping and hopefully my subs and anps will be in thursday and i have it all (semi) completed by saturday and go get it metered!

 

[plexlove]

Oh and jacob is the one who recommended this specific setup to break 60s...he also gave me the name of a guyvwho he said does wonders with these subs...thats where i got the 1.5cubes per sealed from if u werevwondering.

 

[Boomin_tahoe 5,000+ posts]

Enough talk...need pics

 

[plexlove]

Enough .talk...need pics

Wont get pics till weather clears...and 99% of the time i dont bother taking pics...i dont compete either...ill post pics as i progress further into it and if i actually remember to take any...i always get in such a rush i forget.