My '91 Toyota MR2 12inch Sub Box Design --EXPERT OPINIONS PLEASE--

[Scoobydoo 5,000+ posts]

Valid point!
What I should have emphasized when I started to discuss transfer function with hmong on another board is that it wil increase frequency output at the given cars transfer function. That needs to be established and frankly I have not bothered to do the math on it. He is caught up tuning this box to 32hz or whatever and is not factoring any of the calculations into the car it will go in. All theoretical out of environment design.

And no one has yet to eplain how you're gonna fit a ported box tuned to 32hz in the back of that car. And for TWO subs none the less.

if his user name(hmong) is any indication he is probably a 5 foot tall asian guy so he probably has plenty of room to spare once he bellies up to the wheel and puts his booster pillow on the seat

 

[Nighthawk26]

who cares about the passenger as long as the driver is happy. the driver is going to be the one in the car 100% of the time, when there is a passenger he can turn it down if needed

I know but he wants TWO 12's. Next someone here is gonna say you can get 2 behind each seat?

 

[Scoobydoo 5,000+ posts]

I know but he wants TWO 12's. Next someone here is gonna say you can get 2 behind each seat?

i realize that, but he also wants pioneer, i was saying a decent single 12" sub would be a much better option that 2 12" pioneers and it would have the advantage of not pounding your back all the time

 

[Nighthawk26]

agreed

 

[PowerNaudio 10+ year member]

http://www.cardomain.com/ride/402743/5

Here is a link to the 12" ported subwoofer enclosure, i built for my fiero, i did have to push the passenger seat forward about 3" to make it fit properly but it pounded and sounded clean. it could of been done better if i had done a version 2 of it after my friend bought it from me to put in his truck. i didnt get any pictures of it in the fiero, but you get the idea, the fiero has just as much space behind the seats as the mr2 if not less. so im sure you can fit a bigger enclosure then the one i built. if you mount the amplifier on the driver side rather then on the enclosure like i did.

 

[hmong337 10+ year member]

Great discussion guys. Keep the ideas and their reasonings coming.

your top post is kinda misleading as you said 2.2 cubes. I think that is a total number you were shooting for but the way its written looks like per enclosure. Either that or I am too tired to help... lol. Anyway.
I used this calculator

http://www.the12volt.com/caraudio/boxcalcs.asp#wed2

and plugged your numbers into box "Volume Calculator - Wedge Enclosures 2" as it sounds like thats closest to your dimensions you gave and got 1.6^3ft. Knock out woofer displacement and any decent sized port, and your looking at close to 1cube ported box. VERY small for any 12. For better sound quality I would really consider going in the largest sealed you can get per side. When you get small ported box's, you loose alot of the benefit you would usually gain from going larger ported, which is the higher gain @ lower freq.

This is hard to explain if you haven't seen what these number look like on a graph.

1. Go download win isd.

http://www.linearteam.dk/

2. Take a generic woofer as close to what you want to get, (or look up the specs and program them yourself

3. Just play with the enclosure size and tunning and you will be able to SEE what I am talking about, even with a low tunning, in a small ported box, you usually don't see a gain at the lower bass frequency's (at least not more then a sealed.)

-Program a box with a tunning freq of say 30Hz. Make it 1 cubic foot and look at what freq on the graph it cross's the -3db mark. Now change nothing exept volume, say to 3 cubic feet, observe the -3db again, this difference is what I am talking about. Also, you can then make a new project, without closing your old one, see what the plot for the woofer looks like in a sealed box. Look at what the 1.6 sealed looks like next to a 1cube ported.

Before anyone rags on that. YES, WinIsd does not give in car numbers, but NO the numbers are not useless. They are how THE BOX will affect a properly programed in driver. what alot of people forget when they badmouth winIsd graphs:

IF THE ENCLOSURE IS WRONG TO BEGIN WITH, THE TYPE OF CAR BECOMES SUPERFLUOUS INFORMATION.

You are correct. I screwed up on the numbers. I'm not very knowledgeable when it comes to car audio. However, do you think a 1.6cube sealed would be good for what I'm going after? That nice deep low bass...

Hmong, i'm wondering how your depth at the bottom is 14" did you cut your storage boxes.

That's why I'm here... to get second opinions to see if it's really worth cutting out my storage boxes for an audio setup that will pound. Still debating whether I want to hack my car up... I really don't want to but if I could get a nice subwoofer setup by doing so, they're GONE!

hey hmong337 got any more pics of your ride? its pretty sweet. it will be easier for us to help you figure out possible installation methods, if you could provide us with a picture or two of the area you have in mind for these subs to be installed at with the dimensions if possible. video of your ride doing a burn out would help out too. lol

I went and got pics from storage. Will post up in a sec...

lol, i didnt read
imo a single decent 12" sub in a sealed box behind the passenger with about 800 watts would be more than enough for an mr2

i wouldnt want the sub pounding the back of my seat non stop whenever i was driving

I really don't mind... really. I'm a basshead. However, I will definitely be putting a switch to turn the subs on and off.

if his user name(hmong) is any indication he is probably a 5 foot tall asian guy so he probably has plenty of room to spare once he bellies up to the wheel and puts his booster pillow on the seat

LOL too **** funny! I'm actually considered tall for Hmong people and I'm only 5'9! Good that you know a little about my background hahaha.

cheers.

 

[hmong337 10+ year member]

 

[DarkFox 10+ year member]

Deep low bass almost always = large ported with alot of port area //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

Put it in the front trunk and make a cutout for a areo port to extend into the cabin IMO

TBH though I have never seen inside one, so that is a guess, have no Idea how much space yoru working with in the front.

 

[hmong337 10+ year member]

so given my constraints with space, size of box, ect., would it be better for me to go with a smaller sub in an optimal ported box? let's say an 8" in a 1.25 cube ported box tuned to 32hz? from my understanding, it will still hit deep and low but not be as loud?

...i don't want to use the front trunk for anything but storing my amp and spare tire. so that's not an option for me.

any ideas? I want atleast a minimum of 500-600rms in the cabin... low deep bass

 

[DarkFox 10+ year member]

bigger subs generaly handle lower tones better also, but you may be able to get a smaller sub and right box to do it, heck, look what bose does with like 4" woofers. Anyway, usualy the higher power handling subs, still have huge basket structures. But you may be on the right track. I would say to look at kicker. A square 10 for example still has about the same surface area as a 12. but the baskets worry me. Maybe a nice pair of L5 10" subs.

 

[DarkFox 10+ year member]

just as a example you can get a good deal on 2 10" L5s here

http://cgi.ebay.com/2-KICKER-SOLOBARIC-S10L5-10-L5-1800W-SUBS-NEW-PAIR-06_W0QQitemZ250195376052QQihZ015QQcategoryZ3291QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

and a good amp to drive em here:

http://www.sonicelectronix.com/item_6522_Hifonics+BXi+1206D.html

Also, if you call sonic they will usualy price match on the subs and then you will save more money in combined shipping ;-)

 

[hmong337 10+ year member]

in fact, i'm looking at 8" L7's at the moment... rated at 450rms each. but i don't know if they'll hit low and deep even in a ported 1cube.

I found this guy's setup on the mr2ownersclub. he claims to have 1 cube per box. they look awfully small though...

This memeber seems to have a good setup. But his box seems too small for his 8" JL-W7.

 

[hmong337 10+ year member]

any other suggestions?

 

[DarkFox 10+ year member]

at the end of the day you just have to realize, without going into the front, you just dont have alot of room to work with. We have probably exhausted all options without cutting / going into other compartments.

 

[hmong337 10+ year member]

thanks for the replies everyone. i just wanted to make sure no stone was unturned. and after taking a second look in the cabin, 12's are simply going to be way too much work. i even looked into fiberglassing... it's just way too much work for the intended box that i want to build. i guess it's time to scrap this idea and start my research over with two 10's.

again, thank you for all the informative replies.

-hmong337