Sealed or Ported?

['96GAGT]

I did use the search and didn't come up with an answer that would sufficiently help me with the question I have.

My question is what should I go with a Ported Box or a Sealed Box?

Im driving a Grand AM GT. I do not have a fold down seat option so I feel that a Ported box wouldn't do me very good. I have a Ported BandPass and I do not like the way it sounds. Resting against the seat it sounds very bad. But when further toward the front of the trunk (Nearest the lisence place) I get a more deeper sound. I want to be able to have some deep Bass while my Box is against my rear seat.

I have a 2000 Watt Volfenhag Amplifier.

And I have some Boss Ripper series subs 12" Dual Voice coil 1200 Watts Max.

I've been looking at a sealed box It's Dimensions are 13" High 13" Wide and 36" Long. This box is the right size I'm looking for. I'm just wanting to know if it's going to give me the boom that I want. At the time I had the BandPass in my Vehicle I was running it with a 400 Watt 4-Channel Bridged. Running Two 10" MTX subs. It's Max is unknown. All I know is that I didn't like the sound. And I'm looking into this deal.

Which leads me to the same question. Sealed or Ported? I think my new setup would work better in a Sealed box.

[MantaGreen97]

Was this a pre-fab "bandpass" box you were using? If it is, there's nearly no doubt that it wouldn't be any good. Bandpass boxes are probably the most difficult to design and build properly. Like any box, a bandpass box has to be specifically built for the woofer(s) in mind; but unlike sealed and ported boxes, there is very little room for variance/error. For example a sealed box of say 1.5cu.ft.--you can pretty much put any woofer in there and get proper sound out of it. A ported box is a little more picky, as you have to get the size and tuning frequency correct. But a bandbass box really has to be designed well in order to get good sound--I don't think any of the pre-fab ones you see out there do this, even ones made by the manufacturer of the woofer(s).

Note that a properly designed and built bandpass box can actually sound very good, it's just that for the time and effort put in you might as well use a ported box.

Personally, if I were you I'd use a ported box, properly designed for the drivers you are going to be using. Hopefully your amp has a subsonic filter, which should always be used (set at the tuning frequency) with a ported box.

You say you don't have a fold-down seat but that is probably more reason to use a ported rather than a sealed. Since your seat doesn't fold down, you already have less sound pressure able to get into the cabin and ported boxes are typically more efficient at turning watts into SPL.

If you are going to be buying something pre-fab and not either built yourself or custom built, it is probably better to go sealed though, because there is less room for error and less chance that things will sound bad. Another thing to keep in mind, if you do buy a ported box, look for a slot ported one rather than a round ported one (slot ports have less turbulence and less chance of "port noise").

I don't know what the Boss Ripper series are like but first of all don't go by the max power rating, that is irrelevant. I'm thinking those woofers will have an max RMS rating of half of that or less. Secondly, does Boss recommend enclosure sizes for those woofers? If they don't and you want to make or buy a ported box for them, I'd definitely run the T/S parameters through WinISD or something and get the design for the optimal box and either make it or buy something close to it.

[HellishOne]

Your personal preference on the sound goes as far as do you want volume or clean crisp bass. Sealed is goin to give you a cleaner bass bandpass gives you volume. Pesonally I use a vented vega style box it seems to give me a good mixture of both. In my honest opinion I dont like your subs. Boss is a rip off of Bose. But like Mantagreen says get the specifics on the subs optimum airspace and try to find or make a box to those specifications. The only thing that I can think of with where you place the box is that when its against the seat there is no room for the sound to move around it. One option you have thats a bit more drastic is what I had to do with my 96 grand am. I couldnt pull down the seats either. So what I did was find some 4 inch wide ports and I cut out the backing and the foam in the seat. I placed the ports behind the first layer of fabric so they couldnt be seen. I had a 2 door and not alot of people road in my back seat so it was completely unnoticed. The fabric blew out a bit becuase of the air pressure but I dont look in the back seat when I drive.

[GTon9teens]

band pass's are terrible, there FQ response on a graph looks like like you outlined your hand,
i build custom vented enclosures, for SQL or SQ, can do SPL only but an SPL box has no musical quality,
i did a type R 10" tuned for strictly sound quality, i have to say for only a 10 and out hitting 2 15"s, while sounding amazing, its pretty impressive,

heres how i do things, you have 2 12"s i know it is possible for you to sell one of your subs and i can make a vented box with the 1, and not only will it demolish what the 2 sounded like, it will have better SQ
people will disagree im sure, but i have done 4 cars in the last 2 months, and i havn't heard any systems comparable, i did a box for 1 type R 12" that put the JL audio w7 to shame, yeah thats right a $150 vs. a $750 sub
anything is possible it all comes down to the box

This box was Designed for the Alpine Type X, for maximum SPL at a SQ tuning, sounds incredable, its a big box but max SPL was demanded, if you go smaller it takes the DB's down a bit but maintains the same amount of SQ, with ported box's the options on sound are endless
http://memimage.cardomain.net/member_images/4/web/2164000-2164999/2164428_33_full.jpg
http://memimage.cardomain.net/member_images/4/web/2164000-2164999/2164428_35_full.jpg
http://memimage.cardomain.net/member_images/4/web/2164000-2164999/2164428_23_full.jpg

[Hodge]

i did a box for 1 type R 12" that put the JL audio w7 to shame, yeah thats right a $150 vs. a $750 sub


I've heard one of those in a JL ported box and it does hit pretty damn hard it just has the worse high bass i've heard, but hits the lows great. I dono if it blows out the 12" W7... It's really all about the amp you are using.. the JL 1000/1 is quite sick with a W7.

[GTon9teens]

we had 1000w RMS V-12
i've leaned that most all subs sound very different from one and other, what i meant was the SPL was greater on the type R12" then the w7, it seriously put it to shame,

[GTon9teens]

but it is a whole different class of woofer, and if durability is a must, go with a hi end sub, my eclipse TI hits so ****in hard and all day long no problems yet
i was just saying anything id possible with the right box

[Chain]

Personally I like sealed box.... It just has a much cleaner punch sound to it.

[GTon9teens]

the thing is, you can make a ported with just as much punch as a sealed box, and it will hit harder andthe low notes better

[Chain]

Sealed enclosures : A SEALED enclosure will be the smallest,and is the simplest of enclosures and will have good low frequency extension, but might not have the best low frequency extension. If space is limited.
and its a good choice for SQ fans (Sound Quality).

PORTED enclosures (Bass Reflex) : A PORTED enclosure will generally have a better low frequency extension for a given response shape,but would require a larger enclosure. If you made the enclosure as small as the sealed enclosure, but ported it to gain the low frequency response, the output would deviate from the desired flat response.

Ported enclosures are slightly more difficult to design than a sealed enclosure. When using a sealed enclosure, it is difficult to be so far off as to risk damaging the woofers. In any type of enclosure, the woofer relies on the enclosure for damping. If there is insufficient damping, the woofer's cone will move significantly more than it should. The ported box will provide virtually no damping below the port frequency, all of the control will be provided by the woofer's suspension. Below the tuning (port) frequency, it is possible to cause damage to the woofer well before power levels approach the maximum power ratings of the woofer.
common tunning frequencies :
Sound Quality : 20 up to 28 Hz.
Sound Quality Loudness : 30 up to 35 Hz
Sound Pressure LeveL SPL : 40 up to 80 Hz (test tones are played rather than normal music, to avoid Low frequencies, which damages the speaker).
Its commonly used for competition propose. and not everyday driving.(unless you like listening to test tones for everyday driving).

BandPass enclosures (Single Reflex): Bandpass enclosure can sound good and give you a flat response,but most of the bandpass enclosures(in the market), are not designed for a flat response, this means that they are built to produce a large peak at some frequency from 50 to 60 Hz, these enclosures will work well with Rap, but generally they dont sound good with other types of music.
if u use a banpass enclosure. it should be designed specificaly for your speaker.
P.S : its not always recommended.

[Chain]

CALCULATIONS/ FORMULAS

dV = is the required diameter of port in inches.
Fb = is the tunning frequency of the enclosure in hertz.
Vd = is the volume displaced by the driver (woofer)
Lv = is the LENGHT of port in inches.
R = is the internal radius of vent tube
Vb = is the internal volume of the enclosure cubic inches.

PS : to convert cuft into cubic inches

# cuft *1728 = value in cubic inches

Vd = Sd x Xmax

dV>/= 39.37*(Fb*Vd)^0.5

Lv = [(1.463*10^7R^2)/(Fb^2*Vb)] - 1.463

value of R
R = square root (a/3.142)

and "a" is the area of square vent = Width*Hight

changing Round vent to Square vent
A= Pi* (4/2)^2
and Pi =3.142

['96GAGT]

Hes right about the bandpass it sounded good with some very slow paced techno and most rap. I'm looking for something that's going to get some good responce when I listen to my death metal. I've got alot of stuff with double bass action and some faster paced techno/hardcore. Lots of stuff in the 300 BPM bracket. It want it to sound like it's supposed to. I want it to go with the song. Not sound like some jumbled bunch or noise. (which typically happened when I listened to anything too fast with the bandpass) It would make this sick and nasty noise. I don't know if Im communicating what Im trying to say properly. When a song goes BUMP BUMP BUMP that's what I expext to here... I don't want BUUUUUUUUUUMP... ya know what I mean?

[GTon9teens]

i know what you mean, and a poorly designed or prefabbed box will sound like shit
the ported boxes i make are a different story, 2 of the systems i've done, the people listen to techno and metal, and i cant stress enough if its a properly design enclosure it will sound amazing, and you will get alot more SPL off of it
sealed box's hold back so much of what a woofer is capable of doing

the port can throw off everything, it has to be done right,
for example, a type r 12" in a vented enclosure, lets say 3 cubic feet, tuned to 36 hz, i tried it in that box and the port width was 4"x 12", it sounded like pure shit, but the box was not designed for the woofer, it was desiged for a concept PT 12", i redesigned the box for the woofer, 3 cubic feet 36 hz tuning, now the port that is 3.25" by 12" which is what i calculated out to, and that made the world of the difference, the SQ was incredable, when we were listening to pantera the double bass drum was amazing, it never missed a beat and never once sounded sloppy, and thats a $150 sub, (i never go by manufacterers specs, only if you wanna be disapointed)

poorly designed boxes will always sound like shit, you have to design the box to the woofers specs. because every woofer is going to call for a differnt size vent even if your tuning it the same,
the top audio shop here is begging me to come build box's for them because they have heard the systems i have done, because there enclosures are nothing comparable to mine,
my single sub setups will outperform 2-4 sub box setups anyday, in SQ and SPL
although my ported boxes are different then most

if you guys saw what the inside of that box pictured above looked like you would be like whoa

[Chain]

Unless he can find someone to make this perfect ported box that hits as clean as a sealed box... I still say for metal rock double bass hard hitting clean sound..
Go with the sealed box.

I agree my single 12 sealed box with a Treo sub sounds better than most 2 or 4 sub enclosers. But it was professionally designed.

[Lash]

Originally posted by GTon9teens
i did a box for 1 type R 12" that put the JL audio w7 to shame, yeah thats right a $150 vs. a $750 sub


LMAO....what...an 8W7???


Give me a break.

[Hodge]

I agree too ^

[GTon9teens]

it was a 12w7
and my boxes are professionally designed, and graphed out

the type R out hit the 12w7 in my enclosure
i didn't make the enclosure for the w7, had to be a poorly designed enclosure the w7 was in, some guy was showin it off to me, and was not impressed at all,

now if i built an enclosure for the w7 that would be a different story,
which im getting ready to do a w7 12" setup in a 05 benz

i've been doing installs on the side for the last 4-5 months, all it takes is letting someone hear them and they are sold, give me the money to go buy the equiptment then i go from there

every time i do an install i take the vehicle to the shop to let them hear it, and the only thing i hear is "i've never heard that sub sound like that"

[Hodge]

if the amp and the box are good the W7 will blow away competition not neccesarily loudness... but sound quality... that is something no one looks for. it may be loud as hell but that doesnt mean the quality is the best. Please power the 12 with a JL 1000/1.

[Lash]

Originally posted by Hodge
if the amp and the box are good the W7 will blow away competition not neccesarily loudness... but sound quality... that is
Actually...there are a few better SQ subs out there than the W7's. They are $ cheaper too.

[MantaGreen97]

Originally posted by GTon9teens
the thing is, you can make a ported with just as much punch as a sealed box, and it will hit harder andthe low notes better

Agreed. Saying a sealed box has sounds better than a ported box, just isn't true. Perhaps a sealed box sounds better than a certain ported box, but it doesn't apply for every one of them.

You can make a ported box that sounds exactly like a sealed box, only it will more than likely have a little more efficiency and likely a little bit more low end--meaning in fact a better sounding box.

For a ported box it all depends on the design and the proper building of the box as well as proper subsonic filtering on the amp. For sealed it's just a lot easier to get away with even a poorly built box because there isn't much to it. Just a box with a hole for the woofer--doesn't get any simpler than that. Using a subsonic filter is unnecessary since the woofer can't be easily driven into overexcursion in the low frequency area (as can a ported box below its tuning freq.).

And what's with all the formulas? Well they are helpful in understanding the theory, but really just put the TS parameters into WinISD and off you go!

It's not hard to get a box built either, if you're not going to build it yourself. Just go to a good/reputable shop give them your design (from either what you got out of WinISD or perhaps a manufacturer's recommended box) and then tell them "I want this box, how much will it cost to build". LOL.

Otherwise, if you go prefab for example, and can't find a box that closely matches what you need for the ported application, then just buy sealed and forget about it.

[GTon9teens]

it all depends on the woofer every woofer is going to perform completely different from one an other in different sized boxs, that is why a ported box has to be designed exactly off the woofers technical specs,