3 or 4 SA-8's?

[red08yaris 10+ year member]

Ok so I'm gonna run some 8's. The total area for my box will be 15"Hx40"Wx13"D. Will this be enough space to run 4 sa8's ported? The box is going in a hatchback behind the back seat so it will be standing up. Should I mount the subs on the top facing the roof or facing the hatch and what size and placement of the port? thanks

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[pro-rabbit 5,000+ posts]

4 if you use Areo port or 3 if you want to use slot port.

 

[Digital Designs 10+ year member]

I would do them facing up, with the port facing back. That is definitely the best way in my hatch anyway. Also, you should have well over 3 cubes after displacement of the subs/port with a slot port, so you could easily do 4 of them.

 

[pro-rabbit 5,000+ posts]

I would do them facing up, with the port facing back. That is definitely the best way in my hatch anyway. Also, you should have well over 3 cubes after displacement of the subs/port with a slot port, so you could easily do 4 of them.

He only has 3.459ft^3 before any displacements so no. He should run 3 only.

 

[Buck 5,000+ posts]

I you need a design, email me.

 

[outsideshot23 10+ year member]

ya its borderline.. just a hair small for 4 imo.. would only get about .7ish per sub

 

[Buck 5,000+ posts]

ya its borderline.. just a hair small for 4 imo.. would only get about .7ish per sub

Jacob recommends a max of .5 per sub, so that's plenty of room.

 

[Digital Designs 10+ year member]

He only has 3.459ft^3 before any displacements so no. He should run 3 only.

I read the dimensions wrong when I said over 3 cubes after all displacements. Either way he has plenty of space. Those subs dont need more than about .6-.7 cubes anyways.

 

[pro-rabbit 5,000+ posts]

not enough room for 4. I don't care who you are there is not enough after displacements. Not to mention the SA's like a good amount of port area. Do the math if you must. I can do it in my head.

 

[Kangaroux 5,000+ posts]

Jacob recommends a max of .5 per sub, so that's plenty of room.

i hope you mean minimum. he recommends .6-.7 for a min

 

[Digital Designs 10+ year member]

not enough room for 4. I don't care who you are there is not enough after displacements.

I am glad you are backing up your statements with reasoning. //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif I dont care who you are, there is plenty of room after displacements.

OP, something that would help us decide is what kinda amp you will be running?

 

[pro-rabbit 5,000+ posts]

I am glad you are backing up your statements with reasoning. //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif I dont care who you are, there is plenty of room after displacements.
OP, something that would help us decide is what kinda amp you will be running?

Show me the math? I do this for a living and I know it won't work.

here just to help out those that never took basic math.

3.46(rounded up just for you) is what he has before any displacements correct we all agree on this.

Now just divide by 4 and you see you will get .86(round up again) That does not include sub displacements or port displacements yet. I guess if you find some magic room it will work out great.

.6-1ft^3 is recommended for these subs each.

 

[Digital Designs 10+ year member]

Not sure what the displacement of the sub is, but I am going to assume it is NO more than .1 cubes per. Do the max dimensions he gave with a double baffle on top, port could be facing back, 2.75wide x 13.5 high x 21.5 long(L Port). Not sure how much displacement the bracing would take. Ill assume another .1 cubes. That would leave around 2.4-2.5 cubes tuned at like 33-34hz, which should be plenty, depending on how much power he is running. If he is only sending the 4 of them 1200 watts or something, no its probably too small. But the 4 on an AQ2200 or something around there in this box would POUND in my opinion.

 

[pro-rabbit 5,000+ posts]

That "can" work, but unless he has the power it won't work out to well. The port is also on the small side for the SAs. Lets say each sub is .1 so that is .4 all together in a common enclosure. So your down to 3.06. The smallest port I would do would be 13.5 x 3 which is 40.5in^2 port area(ideally I would do more port area). Tunning around 33hz so that would be around 22" long(not exact I'm on my phone) but that is .67ft^3 of displacements which puts you around 2.39(ish) or .59ft^3. I would say its to small for this application. Also you have to take off for bracing and 45s.

 

[Digital Designs 10+ year member]

That "can" work, but unless he has the power it won't work out to well. The port is also on the small side for the SAs. Lets say each sub is .1 so that is .4 all together in a common enclosure. So your down to 3.06. The smallest port I would do would be 13.5 x 3 which is 40.5in^2 port area(ideally I would do more port area). Tunning around 33hz so that would be around 22" long(not exact I'm on my phone) but that is .67ft^3 of displacements which puts you around 2.39(ish) or .59ft^3. I would say its to small for this application. Also you have to take off for bracing and 45s.

Either way, like I said, I think the amp is pretty important in this scenario. My math might be a little fuzzy lol, just doing it in my head and based off assumptions. I am no pro, but I have messed with quite a few subs/boxes.