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Dodgedakotafan
05-30-2010, 01:21 AM
ok i want to buy 4 SA-8's to put in my dodge dakota extented cab, they will be run off a AQ2200

now im not very good at box designing so i wanted to confirm/ask opinions on this box

it will be 3.2 cubes (roughly .8 cubes per sub) with 2 4" aero's with a length of 14.35 inches each, that should make it tuned to 35hz.

does that box sound good? if not feel free to give advice on this box. Thanks!

hatedonmostly
05-30-2010, 01:27 AM
Depends on who you ask...I'd say too little port area

Dodgedakotafan
05-30-2010, 01:34 AM
what do you suggest i do for aeros then? im not really sure, i was just taking a stab in the dark on this one.

i forgot to add, this will be daily driven, id like to have it sound as good as possible on all types of music, from rap/hip hop to metal

supermaxx123
05-30-2010, 01:36 AM
I'd do 4 of those ports

supermaxx123
05-30-2010, 01:37 AM
I also hope you took into account the subs airspace along with ports, pretty big subs. should sound really good though with your airspace/tuning and proper port area.

Dodgedakotafan
05-30-2010, 01:44 AM
yeah i took into account of sub displacement, i figured about .1 cube per sub, overall the box should be roughly 3.7 cubes before displacement.

you think i should do 4 4" aeros? wow that seems like alot. that would make the aero's 31.63 inches long though, thats far too long

well honestly im using this calc http://www.carstereo.com/help/Articles.cfm?id=31 so when i type in the enclosure volume i should be typing in the cubic feet after displacements correct?

supermaxx123
05-30-2010, 01:46 AM
seems like a lot but it's what needs to be. You might be safe with 3, personally i'd run 4. this sub moves some air.

Dodgedakotafan
05-30-2010, 01:50 AM
ok so if i do a 3.2 cube box (after displacements) and use 4 4" aeros, the calc is telling me i need to make the aero's 31.63 inches long, and i just dont have the room for that and i would rather not have the ports outside the box. hmm im at a loss of what to do.

supermaxx123
05-30-2010, 01:52 AM
try 3, would be better than 2.

Dodgedakotafan
05-30-2010, 01:55 AM
hmm even for 3 4" aeros it would need to be 22" long for a 35hz tuning. i wish i was better at this, this is only my second time designing/building a ported box

Bumpin' Goalie
05-30-2010, 01:58 AM
Aeros are tricky like that. To achieve anywhere close to daily/low tuning and maintain "proper" port area length is CRAZY.

PSP Flared Aeros help with the flares. Though still hard to judge. One 12-14 of port area via PSP Aero for ~ 2 liters of Displacement seems to work well for me so far.

supermaxx123
05-30-2010, 01:58 AM
i had the same problem, had to tune to 37hz, sometimes space can be a challenge. only fix would be passive radiators but unless money is not of limit, i'd say try a higher tuning.

Dodgedakotafan
05-30-2010, 02:00 AM
hmm yeah, right now i have an AQ sdc2.5 tuned to 38hz, i like the way that sounds, so i might try tuning to that again, i just wanted to try something different.

Bumpin' Goalie
05-30-2010, 02:04 AM
hmm i may just go with a slot port design, seems simpler unless i can figure something out with these aeros

Have SD and Xmax on the SA-8's? Can't recall them.

SD (in CM^2) * XMAX (in CM) * 2 / 1000= Displacement in Liters.

1 4" Aero has 12.56 port area.
2 4" Aeros have 25.12 port area
3 3" Aeros have 21.195 port area.

Those would be your best bets depending on liters of displacement.

supermaxx123
05-30-2010, 02:06 AM
can't expect them to sound the same even at the same tuning. maybe try using 3 subs and 2 ports.

Bumpin' Goalie
05-30-2010, 02:08 AM
Also, the higher you tune, the less port area needed in most cases...

Maybe bigger box? Can help to an extent...

supermaxx123
05-30-2010, 02:10 AM
Also, the higher you tune, the less port area needed in most cases...

Maybe bigger box? Can help to an extent...

i was going to suggest bigger box but i dont know if he has the space. port outside may also be the last resort.

Dodgedakotafan
05-30-2010, 02:10 AM
can't expect them to sound the same even at the same tuning. maybe try using 3 subs and 2 ports.

only thing about 3 subs is that i cant maximize my amps potential due to the way i would have to wire them, but i wont leave it out of the picture just yet.

Dodgedakotafan
05-30-2010, 02:12 AM
i could possibly do a slightly bigger box, not much bigger though, afterall this is an extended cab truck and i still need room for amps and stuff :P

hmm i just might have the ticket :P

4.5 cube box (i dunno if 1.25 cubes per sub is too much though) with 3 4" aeros 12.71 inches long should give me 35hz and hopefully enough port area

Bumpin' Goalie
05-30-2010, 02:12 AM
What is Xmax and SD....?

It'll help you know what ports/how many ports you need...

supermaxx123
05-30-2010, 02:15 AM
only thing about 3 subs is that i cant maximize my amps potential due to the way i would have to wire them, but i wont leave it out of the picture just yet.

they have dual 4ohm and dual 2ohm subs, amps also run cooler at higher impedance but i also know how people like to get their moneys worth.

Dodgedakotafan
05-30-2010, 02:21 AM
I cant find SD but the xmax i believe is 16.5

Bumpin' Goalie
05-30-2010, 02:25 AM
I cant find SD but the xmax i believe is 16.5

Most 8's are 180-210 so we'll say 200...

That puts us right around 2.7 liters of displacement.

I'd say 2 4" flared aeros could work.


pm "michaellane" I believe he has some hands-on experience with SA-8's using aero ports.