Ported vs. Sealed boxes
 

I'm designing a custom sub enclosure for my car, and I'm curious as to your preferences as far as sealed vs. ported boxes go. I know ported is louder but sealed hits harder, but I would like some more information.

And along those lines, when desiging the box, is it better to opt for the top or bottom end of the recommended range? I noticed there's a little bit of overlap in the recommended volume for sealed and ported boxes, so would I be able to make a compromise and plug the port? Like, I'm looking at 2 Alpine Type-S 2ohm 10s and the sealed size is between 0.65 and 1.5 cubic feet, and ported is 1-1.75. So, in theory, couldn't I make a box that's, say, 1.5 cubic feet or so with a port and seal the port to switch between?

One last thing. The recommended port for this sub is said to be 3 in diameter and 9 in long. Does orientation matter, as far as axies are concerned? Like, should the port be parallel to the "line of fire" of the sub, or does it matter at all?



Thanks in advance,

Jake

Sealed for me. Prefer the quality over more boom for less buck. Nothing like two 10"s in a sealed box.

what do you listen to would help you in decide in what you want...

if you are going to make a box with port and cap. Make the cap same material as the box with gasket..to ensure air tightness...

do not make the line of fire same as the port....the only way to know is to test various boxes with different size port and location...if you are beginner you won't be able to tell the difference...various harmonics...if you want more let me know on this subject...

if you want to impress people inside your car get sealed...or if you want to wake up your neighbors...get ported...

I would choose sealed...

All things being the same, sealed tends to play lower, ported tends to play louder. If you want to go ported it is recommended that the port lie in the same plane as the driver. I am a sealed fan because they are easy to build and give the smoothest overall sound, they do need more power than other box designs however. Don't try to make a box that is designed for 'multi-purpose' (sealable port or something like that.) Just pick a design and throw your T/S params into some software, play around with it. There are some free programs available on the web (ISDpro?) and big time programs for big time bucks (Termpro).

Box design depends more on the subwoofer and on the car than to preferences. Properly designed ported boxes can sound alot better than asealed box with some subs. And some subs just flop around like crazy in any sealed box.

For type S's in a civic I'd really say make a 1.5 cu.ft common chamber sealed box. It'll give you good power handling and pretty good sound. You'd be happy for sure with that setup

Each sub is going to be on a different side of the trunk in individual boxes, so 2 1.5 cubic ft. boxes, right?


And yeah, Devani, I'd love some more information on this. All I know about this area is hearsay, I'd like to have some solid info to go off of.

Two 0.75cu.ft boxes..

Thats good to here...maybe thats why mine sound so good. I don't know the exact measure on my box tho....bought it when I didn't know much about stereos, still not a pro at it.

I love my Type-S 12s, they're in a sealed box running of a 600watt max V12 Alpine amp(like 280 2 channel) and they can shake the front windshield quite a bit(and the rear definately)

Whoo. Post #400.

But the Alpine spec sheet recommends a sealed box volume of 0.6 to 1.25 cu ft. It looks like that's per sub, not per pair, as per the other specifications provided. (wow, that's a lot of "per"s) mohawkboom, you said two 0.75 cu ft. boxes, but that could be intrepreted either way. If the recommended specs are per pair, then that's at the top end of the range, but it's at the bottom if it's single.

I'm sorry if I'm not making much sense, I'm looking for comprehension rather than straight-up dimensions.

So I guess you're implying that it's best to err toward the lesser side of the range. And, of course, I'm assuming that figure does not account for the displacement of the sub itself.


OK, now a few other questions. The design is drawing to a close, I'm working on more modeling the actual components rather than the assembly itself, i.e. drawing the amp, and the hinges, etc. and this is where I need to start thinking about the construction aspect. Any idea where I can get some specific information on the carpeting process? I'll check and see if there's a DIY somewhere, but I've never seen one.



Jake

call Dusty at lakeside audio in Conroe www.lakesideaudio.com he built my last 2 boxes and the man knows his shit he can explain the reasons to you best

Any other place online? I'd rather just read the information somewhere...

www.jlaudio.com has some really good information about boxes, its all technical stuff.

http://www.carstereo.com/help/Articles.cfm

Use to design the box..But the thing is to use any reputable software to design your sub...

This should keep you busy for a while....:rofl:

a good program if you can get your hands on it is called bass box pro 6.0... thats what i used for my box, and if you change anything such as orientaion of the speaker, length of the port, size of the port, it will throw you box off. I just built a custom shapped box for my trunk and needless to say its a pain in the butt.

Naw, I'm gonna use Inventor 10 to design the system, although it's a little (by a little I mean extremely) excessive. I need to put some pictures up to show what this program is capable of. I think that JL site may have some of the information I'm looking for.


Oh, and TransformedBG, that "Sign The We Want 7thGen Back Ballot" Link doesn't work. Ten bucks says the thread was deleted.

But yeah, I also am displeased with the changes made on this site.

nevermind

Just goes to show the length the new mods will go to to get there way.. But when theres no more 7thgen'ers on here sucks to be them.. hell ill buy it for 10 bucks and get it back to its origanal form.. Ive been thinking about making an new websit and calling it 7thgencivic_ver2.com

Hey, I'm in. I imagine you can get a pretty good following. Might want to get a catchier name, and you're golden.

Wonder how long it'll take this thread to get deleted? Time now, 5:00 on monday. The natives are growing restless.

What are you talking about?




Ahhhh... I see. This is an allusion to a previously deleted post for "offensive content" as perceived by our illustrious new owners. Wonder if we'll all be forced to flood the 7thgen section of HT? Is there anywhere left, or is this site the last bastion of 7thGen enthusiasts? Maybe its time for a little capitalism here... Competition can do amazing things.

well my sig thread was up for about 3 or 4 days.. so we will see, maybe we just got lucky and have a name like.. box design lol. vs TO THE MODS lol.

at work i relized all the sealed subs sound the best theyr all 10 and 12s the p 1 2 and 3 all sound good in sealed the alpine type R sounds horrible in the vented box i dont know why

Perhaps we should have the Box Design Club... Something like an underground movement. I'm in.

What do you mean it sounds horrible? I had 2 alpine type R 12's in a sealed box and they didnt sound TOO bad. I popped the cash for the alpine boxes that they make specifically for the type r, to exact specs, and it made the BIGGEST difference. It honestly sounded like I had 2 completely different 12's. Im a big fan of ported boxes now, however, like its been stated previously in this thread, some subs sound better in different enclosures. The type r's however sound WAY better in a properly tuned ported box.

My current setup is a single Pioneer SPL sub with the alpine ported box and I dont think Ill get rid of this setup for a while. It sounds AMAZING. I listen to lots or hardcore and screamo, so I dont like booming bass, but when you put in some hip hop and turn the bass up, that sub is amazing! Im really picky about my setup and tuning so it sounds just right, and this sub is one of the best Ive heard other than my W6's that got jacked out of my car. :(

btw...both setups I was running a JL 500/1. :tup:

and on another note, when I used to have my Rockford Power HX2's they sounded WAY better in a sealed box. same with the W7. so it all depends on the sub.

yea, i have 2 12" alpine type-e with a 700W mono alpine amp in a sealed box. it sounds amazing, and with all the dynamat i put in the car has very little rattling. not to mention the sound is completely contained in the car, a lot of my stupid friends think my subs suck, which thier E's so yea kinda, but its just cuz all the sound is trapped in the car. I know a lot of guys that go for the ported boxes with thier sony xlpods. whatever man, i love my sealed box, those E's pound hardcore

Sealed Enclosure:

pros:
- Small Size.
- Harder to reach the mechanical limits of the sub.
- Calculating volume of the enclosure is easier.

cons:
- Lack of bass extension

Vented Enclosure:

pros:
- Bass extension
- Bass near resonant frequency rises in volume considerably (this can be a con too depending on your tastes)

cons:
- Calculations for volume are dependent on resonant frequency desired and subsequent port sizing. (You must add to box size as if the port were a solid cylinder, unless the port were external to the box.)
- Small diameter ports can cause whistling, while large diameter ports require alot of space. (Bose has a subwoofer in which the enclosure is the port. At 12 inches in diameter the port comes out to 12 feet!)
- Port diameter and length directly affect the resonant frequencies. (I consider general recommendations to be risky business.)
- Chance for mechanical blow out rises exponentially below the resonant frequency. (Buy an amp that has an adjustable sub-sonic filter in order to help preserve your subs)
- Box typically requires double or more volume compared to a sealed enclosure. (I've seen subs that require 5x the volume of its sealed counterpart)

If i think of more, ill add to the list here.

P.S. Feel free to contact me if you would like custom calculated enclosure sizes and port sizes. Just mention the make and model of the sub.