240sx box help.

[KTMrida4life 10+ year member]

Noise as in port noise?

That shouldnt be an issue.. its in my trunk. If it makes enough port noise for me to hear it from the drivers seat thats a problem..

What do you mean by glass work? Fiberglass? How would that help?

 

[IonRL205 10+ year member]

Your best bet is to just go with a 12. You'll be better off with a properly ported 12 than you would with a cramped 15. To give you a little idea, my box for my 15 is 3ft³ (pretty much the minimum you would want for a 15) @ 31 hz and the dimensions are 34" wide, 17" tall, 17" depth (from front of box to back)

 

[KTMrida4life 10+ year member]

Your best bet is to just go with a 12. You'll be better off with a properly ported 12 than you would with a cramped 15. To give you a little idea, my box for my 15 is 3ft³ (pretty much the minimum you would want for a 15) @ 31 hz and the dimensions are 34" wide, 17" tall, 17" depth (from front of box to back)

That will almost fit man. I can make the box at least 35 inches across (maybe taper out to 40ish) and 16" deep by 12" tall. Thats over 3 cu ft... I think I can make this work. I really need to get in touch with a good box designer and give him some dimensions and see what he can do.

BTW, the amp Im getting is 1500W. I dont know of one 12 in a decent price range that can handle that.. probably a bit too much power for a 12 anyway, and I cant afford 2 12s. Why I thought about the 15.

 

[kev28 10+ year member]

my fr man he friend has a nissan 249sx he walled his you should consider it look on youtube under team ridiculous soundz seans first day back you will see

 

[KTMrida4life 10+ year member]

my fr man he friend has a nissan 249sx he walled his you should consider it look on youtube under team ridiculous soundz seans first day back you will see

Took some searching but I finally found it.. Im good man. LOL. Thats the older 240sx, the S13. Only a year between mine and it but it is a totally different car. I think its actually a hatchback.

Anyone know any good box designers? Im going to make another thread.

 

[KTMrida4life 10+ year member]

Looking for something like this.

BTW, google sketchup is amazing. Very fun and pretty easy to use.. wish I knew more keyboard shortcuts and how to do other things than draw rectangles and push/pull.

Thats a very basic idea of what Im thinking I can do. Box is 35" at the rear, extends out 10", then opens up to 40". Box is 12 5/8" tall. Accident on my part.. forgot to figure in thickness of MDF. No idea how much airspace.. would this even work acoustically? Does it matter what shape a box is?

 

[Phoenix Risen 10+ year member]

BTW, the amp Im getting is 1500W. I dont know of one 12 in a decent price range that can handle that.. probably a bit too much power for a 12 anyway, and I cant afford 2 12s. Why I thought about the 15.

there are a lot of 12s out that will take 1500, im going to be putting ~4500 to mine once its built....

as because the dimensions you can get are 3 cubes that does not mean that you have the space for the port, bracing, and the sub. and can still end up with 3 cubes.

and btw, pretty much any 15 on the market that will take 1500 the 12'' version will do the same.

and in ported enclosures shape does matter a bit, but at your level youll not really notice it.

 

[KTMrida4life 10+ year member]

and in ported enclosures shape does matter a bit, but at your level youll not really notice it.

Not sure why I was doing the angles, just gonna make for a PITA later. Heres a revised version

Inside dimensions for the rear section are 10" x 33.75" x 11.375" (height) and for the front section 40.75" x 6.5" x 11.375". I did the math and got 3.95 cu ft. Sub displaces .24. Leaves me with about 3.7 cu ft before bracing and port. Is that enough? How much displacement does a port usually take up? I may be able to make the box bigger.. I know I *can*, Im just scared I wont be able to get it into the trunk. My head would probably explode in anger... lol

Also, this is about as far as I can get right now. Im confused at this point, need to talk to someone who knows their stuff or do a ton more reading. Im confused about where to put bracing and the "tunnel" (right word?) that I keep seeing in your typical box diagram... like this.

Do I need to still do that if I use a PVC port or is that little right angle tunnel only if your using a slot port? Noob questions here someone help me out...

I made enough room to mount the sub on top of the box firing upward and I want the port (PVC pipe I guess) over to the side, hopefully firing up through one of my rear speaker openings and subsequently my rear deck. Thats the plan anyway... Im going to measure my trunk again tomorrow a little better, I did it in the dark last time with a flashlight.

Also, where do I need bracing inside the box?

 

[Phoenix Risen 10+ year member]

ok, you dont want to have right angles in your enclosure if you can help it at all. the inside surfaces should be as flowing as possible.

the reason there is a bend in the port is because it has to be a specific length to get the required tuning. and often times that length is longer than any one wall in the enclosure, and yes the same rule can and will apply to areo and pvc ports (thats the big reason i dont use them..

the last enclosure i built for my xxx 15 was 3.5 cubes net and tuned at 36. it was just over 5 cubes gross before all displacement, so ports especially larger ones will take up a lot of space. which means that your 3.9 cubes most likely is going to be too small for a 15 once things are all said and done.

i still say the best be is to go with a strong single 12 and call it a day. or even a monster 10...

running a smaller sub in the proper sized and tuned enclosure will get greater results than running a larger sub in a cramped poorly designed one.

 

[KTMrida4life 10+ year member]

ok, you dont want to have right angles in your enclosure if you can help it at all. the inside surfaces should be as flowing as possible.
the reason there is a bend in the port is because it has to be a specific length to get the required tuning. and often times that length is longer than any one wall in the enclosure, and yes the same rule can and will apply to areo and pvc ports (thats the big reason i dont use them..

the last enclosure i built for my xxx 15 was 3.5 cubes net and tuned at 36. it was just over 5 cubes gross before all displacement, so ports especially larger ones will take up a lot of space. which means that your 3.9 cubes most likely is going to be too small for a 15 once things are all said and done.

i still say the best be is to go with a strong single 12 and call it a day. or even a monster 10...

running a smaller sub in the proper sized and tuned enclosure will get greater results than running a larger sub in a cramped poorly designed one.

I still think I (or more likely a box designer) can make this work.

Good to know about the right angles, I thought about that. I will have to figure something out there.. is there any size requirements for a port (PVC, length, width) or is just whatever it takes to achieve the correct tuning?

Im going to measure my trunk again.

 

[disturbed471985 5,000+ posts]

Member guys he has a budget of under 200 bucks.. There are not many 12's of quality out there for that price that can take a solid 1500 daily... PM pro-rabbit or Ram_Designs or DonH for a box design..

Here is one that will - http://www.ebay.com/itm/American-Bass-XFL-1222-2000W-12-XFL-Sub-Car-Subwoofers-Dual-2-Ohm-2000-Watt-/260855236550?pt=Car_Subwoofers_Enclosures&hash=item3cbc2f07c6

 

[audiobaun 5,000+ posts]

I have a 90 model 240sx, and I ran a pair of Audiobahn AW1006t 900rms 10s in there in a single enclosure with two chambers ported with 1.6cuft perchamber, and them off of The Audiobahn 18001dt mono amp with an oldschool USA US Acoustics Series II 4080 on a pair of Kicker 6.5, and ks25 tweeters, and a pair of 5.25 in the rear pillars, and sounded GREAT! I built a false 3/4in floor to level out the surface across the rear floor.Get rid of the Cheap Fiber board cover.I also recommend putting deadner on the bottom of the tire well and the rest of the area, as the road noise is pretty loud.I ran 4ga power supply, and had no issues with a small kinetik battery.Though, no real room left for anything, and nothing exposed visable from outside the vehicle .All in Hatch space.I recommend tens, for the air space you have.Sounded Great for me!//content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 

[KTMrida4life 10+ year member]

Thats what I have =\ Granted their not great 10s but theres still 500W going to them.

If I cant do 90 degree angles... what can I do instead? Could the outside of the box be a 90 degree angle, but on the inside I screw/staple/attach some very thin plywood bent around the corner to smooth it out?

I know I could do just a bit rectangle, and I still can. Just trying to avoid leaving about 10 inches on either side of the box..

 

[disturbed471985 5,000+ posts]

Yes u can just use 45's in all the corners problem solved.

 

[audiobaun 5,000+ posts]

What tens do you have again? I still have my box that I made myself, and can measure it.I just made it out of 3/4MDF,Rectangular, and sealed it in and out, and made my own ports out of PVC 2 1/2in x 7 3/4 deep, and sealed the outside with flexstone paint.I fired mine straight up at the glass.Pushed the sub box all the way to the left side for all the amps, and power wiring on the right.Whos to say it needs to be directly in the middle?Didnt seem to make much of a difference in sound either way moving it around ..to me though.You can also tilt the box at that angle, and put support L brackets/bracing under it?