# 12 Ported vs 15 Sealed - SUV



## Hardwrkr

Considering cabin gain won't help me much in an SUV which would be the better option between the two for decent bass? I'm trying to keep the enclsure under 2cu.ft and power under 1000rms. Thinking either a 15wGTi (used) or a MB Quart PWE-354 sealed ~1.5 or a Type R or equivalent 12 that will work well small ported in the same size enclosure.

Mostly an SQ install but I want some decent bass response as well.


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## basshead

15 sealed!

the 12 might give a bit more output at a specific frequency but since you're looking at SQ go sealed specially that it will add more delay if you ported.

In a Dodge Caravan, i got 136db off 900w with my w15gti in a 2.25 sealed box. I know for SPL guys this is nothing but enough to get instant ringing...


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## sangellga

basshead said:


> 15 sealed!
> 
> the 12 might give a bit more output at a specific frequency but since you're looking at SQ go sealed specially that it will add more delay if you ported.
> 
> In a Dodge Caravan, i got 136db off 900w with my w15gti in a 2.25 sealed box. I know for SPL guys this is nothing but enough to get instant ringing...


I agree. If you are leaning more towards SQ go with the 15 sealed. Also, as I posted earlier, I hit 141.7 using 2 x 12s sealed and 1000 watts, and that was in a Ford Explorer SUV. Sealed can give decent SPL with the right driver and enclosure. Again 141 is not that high to an SPL chaser but it is FAR louder than needed for listening and more than adequate for those random volume demonstrations. Good Luck!


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## Hardwrkr

Thanks for the input. The reason I'm asking is because looking at the JBL website for the w15GTi in the recommended sealed 1.5 it looks WAY quieter compared to a 12 in a 1.5 ported enclosure. I'm assuming this is due to cabin gain?


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## sangellga

No problem at all. Not sure how much enclosure design knowledge you have so please do not be offended if I provide more information than need.
I doubt the JBL recommendations are considering cabin gain since this factor would change based on the vehicle. The vented enclosure will be louder at the tuned frequency due to the design of the enclosure. A vented enclosure is able to utilize the sound waves generated from the back of the speaker cone. This typically results in volume increase of 3db at the tuned frequency. If you are looking for SQ then I would recommend something around 33hz tuning but that is a personal opinion only. Now while these enclosures can be very musical and accurate they are *TYPICALLY* not as accurate as a sealed enclosure. Most are considered “boomy” since there is a boost in volume at the tuned frequency. Also, frequencies below the tuned frequency tend to roll of faster and there is the danger of hyper extending the woofer on frequencies below the tuned frequency. A subsonic filter is recommended if you are using a high power amp. Cabin gain can be factored in *IF* the enclosure is tuned to the cabin’s resonance frequency but for SQ I would not recommend this approach. 

Now, on the other hand sealed enclosures isolate the sound waves from the back of the speaker inside the enclosure. This typically results in a -3d volume decrease but only around the tuned frequency of the comparable vented enclosure. They typically have a flatter response curve and more accurate low end sound reproduction. Typically the sealed enclosure is more accurate and tends to have a “warmer” sound than a vented enclosure. An additional added benefit is that the sealed enclosure provides re-enforcement of the woofer extension providing high power handling with less risk of damaging a woofer.

So I do not start a enclosure design war, please understand much of this is my OPINION! I have heard vented enclosures that sound VERY accurate but this is not the norm. Especially if you are new to enclosure design and are not willing to do a lot of trial and error to get just the right sound. I have used both designs, but I typically like the sealed enclosure better.
I would advise that you keep asking questions and perhaps even try both with your JBL. A 1.5 cuft enclosure sounds small for a vented 15 but I am not familiar with the JBLs. If that is truly accurate then you should be able to build one of each fairly cheaply and easily to see which you like the best. Then sell the other one to a buddy.

Just my 2 cents, I look forward to hearing the thoughts of others and if I am incorrect in any of my observations please post a correction as I am a hobbyist, not a professional.


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## Hardwrkr

JBL gives both a "In Car" and "Out of Car" response curve so that's what I was going on.


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## sangellga

Gotcha! Keep us posted on your decision.


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## 60ndown

15jbl


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## ChaunB3400

12 ported


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## Jmirage

12 Ported, all day long, flatter when tuned correctly. Every time I go sealed, I miss that low end (25-35 hz) that I get with the ported enclosure. 

Definitely consider Diamond D6's, Alpine Type R's, and Mach 5 Ixl's for that sized ported enclosure.


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## ChaunB3400

Jmirage said:


> 12 Ported, all day long, flatter when tuned correctly. Every time I go sealed, I miss that low end (25-35 hz) that I get with the ported enclosure.
> 
> Definitely consider Diamond D6's, Alpine Type R's, and Mach 5 Ixl's for that sized ported enclosure.


exactly


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## ChaunB3400

honestly when most ppl say sq, they mean for daily, not comp sq, and none of the subs mentioned would I use in a comp sq setup


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## Jmirage

Hardwrkr said:


> Mostly an SQ install but I want some decent bass response as well.


I think that means the only thing that isn't wanted is a one note wonder.


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## RyanM923

2ft^3 isn't enough room for a single ported 12"er, especially if you're wanting to tune low. Stick to the single sealed 15"er IMO.


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## Eastman474

Jmirage said:


> 12 Ported, all day long, flatter when tuned correctly. Every time I go sealed, I miss that low end (25-35 hz) that I get with the ported enclosure.
> 
> Definitely consider Diamond D6's, Alpine Type R's, and Mach 5 Ixl's for that sized ported enclosure.


x2 ^


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## RyanM923

Eastman474 said:


> x2 ^


Too bad he doesn't have enough space for a ported 12...barely enough for a ported 10.


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## Jmirage

RyanM923 said:


> Too bad he doesn't have enough space for a ported 12...barely enough for a ported 10.


Alright, we get it, you don't agree, so you feel like you have to keep repeating yourself. Great, but I will have to refer you to this guy who uses 2ft3 as a standard airspace for each 12" sub...



ramdesigns.com said:


> RAM Designs: Your Source for Quality Box Plans
> Standard Box Volumes and Tuning Frequencies
> As of right now I will only be supplying dual 10", dual 12", dual 15", and single 18" box designs.* If you want something different, feel free to go to the "Need a Custom Box?" tab*with a custom box design request.* As time allows, I will be adding other boxes with updates to be written in the "Newly Added/Blog" section of the site.
> 
> Dual 10" = 2.25ft^3 @ 33hz
> 
> Dual 12" = 4ft^3*@ 33hz
> 
> Dual 15" = 7ft^3 @ 33hz
> 
> Single 18" = 6ft^3 @ 33hz


It is possible that the guy who owns that site has no clue what he's doing.


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## Mathew

Jmirage said:


> Alright, we get it, you don't agree, so you feel like you have to keep repeating yourself. Great, but I will have to refer you to this guy who uses 2ft3 as a standard airspace for each 12" sub...
> 
> 
> 
> It is possible that the guy who owns that site has no clue what he's doing.


Lol! Shut down! "standard box volume" is kind of funny anyways, especially from a "professional" who said he was "disturbed by the amount of prefab boxes out there"

I'll go with the no clue theory.


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## Cruzer

Either should be fine. ported gives the better low end, with no noticeable difference in SQ imo. but u cant go wrong with sealed for sq, especially with a 15

idk who said 2 cubic foot ported for a 12 isnt enough. most 12s dont need that big


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## RyanM923

Jmirage said:


> Alright, we get it, you don't agree, so you feel like you have to keep repeating yourself. Great, but I will have to refer you to this guy who uses 2ft3 as a standard airspace for each 12" sub...
> 
> 
> 
> It is possible that the guy who owns that site has no clue what he's doing.


It's not about not agreeing, it's about a good ported box for a 12" sub not being capable with his original requirements that he posted. The OP stated that he wants to stay under 2ft^3 total volume, so you're looking at a good deal less after sub and port displacement. you can barely get a solid 10" ported box to be under 2ft^3 gross air space.

As far as the standard box sizes go, that's 2ft^3 per sub in a shard chamber, where you can get away with using less volume per sub. It'd be the same as using 2.25ft^3 if in separate chambers. Several 12" subs work fine in 2ft^3, or even less, when by themselves. The SA12 is a great example along with several Treo woofers. Others thrive in larger boxes, such as the HDC and other mid-level qts woofers that people port to get big gains out of. Nothing can be perfect for everything, but a 4ft^3 common chamber box for a pair of 12" subs is nothing to be baffled or worried about.



Mathew said:


> Lol! Shut down! "standard box volume" is kind of funny anyways, especially from a "professional" who said he was "disturbed by the amount of prefab boxes out there"
> 
> I'll go with the no clue theory.


There's nothing wrong with a generalized standard box size that will work with 90%+ of the woofers out there. Obviously if you were to need something different you can send me a message for a custom design made exactly how you want/need.


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## subwoofery

RyanM923 said:


> It's not about not agreeing, it's about a good ported box for a 12" sub not being capable with his original requirements that he posted. The OP stated that he wants to stay under 2ft^3 total volume, so you're looking at a good deal less after sub and port displacement. *you can barely get a solid 10" ported box to be under 2ft^3 gross air space*.
> 
> As far as the standard box sizes go, that's 2ft^3 per sub in a shard chamber, where you can get away with using less volume per sub. It'd be the same as using 2.25ft^3 if in separate chambers. Several 12" subs work fine in 2ft^3, or even less, when by themselves. The SA12 is a great example along with several Treo woofers. Others thrive in larger boxes, such as the HDC and other mid-level qts woofers that people port to get big gains out of. Nothing can be perfect for everything, but a 4ft^3 common chamber box for a pair of 12" subs is nothing to be baffled or worried about.
> 
> 
> There's nothing wrong with a generalized standard box size that will work with 90%+ of the woofers out there. Obviously if you were to need something different you can send me a message for a custom design made exactly how you want/need.


There's a lot of 10" sub that works beautifully in less than 1cuft ported (total volume). The Dayton HO is 1 great example. 

Well most know that you need to compromise something in order to get to your goal. 2cuft might not be enough for low low tuning but he might be alright with a tuning freq around 33Hz-35Hz 

Kelvin


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## RyanM923

subwoofery said:


> There's a lot of 10" sub that works beautifully in less than 1cuft ported (total volume). The Dayton HO is 1 great example.
> 
> Well most know that you need to compromise something in order to get to your goal. 2cuft might not be enough for low low tuning but he might be alright with a tuning freq around 33Hz-35Hz
> 
> Kelvin


There are always exceptions to the rules. The Mach 5 IXL is another, along with a few TC woofers(the OEM10 comes to mind). The point that I'm making is that there is a far greater number of 12" subs that would not work with a 2ft^3 gross box, than those that would. A 2ft^3 gross box for a ported 12" woofer is by no means normal or common.

I can see if the OP wanted to go with a single 4" aeroport to save some space, but I don't see anything >1.5ft^3 net happening with a slot port. You're either going to have to sacrifice port area or box volume in this case


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## subwoofery

RyanM923 said:


> There are always exceptions to the rules. The Mach 5 IXL is another, along with a few TC woofers(the OEM10 comes to mind). The point that I'm making is that there is a far greater number of 12" subs that would not work with a 2ft^3 gross box, than those that would. A 2ft^3 gross box for a ported 12" woofer is by no means normal or common.
> 
> I can see if the OP wanted to go with a single 4" aeroport to save some space, but I don't see anything >1.5ft^3 net happening with a slot port. You're either going to have to sacrifice port area or box volume in this case


That's why Audio is fun. If one driver doesn't fit your requirements, then just sell the driver you have and find one that does. 
Don't know how loud the OP likes to listen but I'd also suggest a 12" ported. 

The IXL is a good suggestion. The IDQ 12 v.3 fits your need too. Acoustic Elegance has a few drivers too and might use your power better since they're so efficient (not sensible ). It all depends on how much power you're going to send and how much Xmax the driver has - the more you have (power or Xmax), bigger the port will be (bigger port = longer port for the same tuning) 

Hope that helps, 
Kelvin


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## RyanM923

Just ran some numbers, and it looks like you could do something like 1.25ft^3 ~32hz with a slot port. The port are would still be smaller than idea though.


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## decibel

my opinion ported 12"
and it can be an Fi Btl 12


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## Chaos

As much as I like the sound of a sealed box most days, there are times that I just want to turn it up and slam, which is when I miss having a ported alignment. 

If it were me, in an SUV, I think I would go with the ported 12" and eq the boom out of it for daily driving. That way, you can have your sq but still be able to pump the bass up when you wanna.


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## Wild Child

The sealed enclosure will give you more low end while ported will provide more output at Fs.


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## RyanM923

Wild Child said:


> The sealed enclosure will give you more low end


Not true in most cases. If tuning very high or using a prefab box(let's say 40hz tuning), then yes, there's a better chance that the sealed box will eventually provide more output once down around 30hz or so(also sub dependent). But build a proper ported box and tune it to around 30hz, and you won't see even the best sealed box subs surpass it in output until you're pretty much out of the audible range.


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## Wild Child

I stand corrected, I meant to say "better low end extension". Meaning 20hz and lower. Also when I said Fs, I meant F3. Sorry wasn't thinking this morning, been a while since I've talked speakers. At F3 and above (to a point) a ported enclosure will have more output, below F3 the sealed will have more output. Don't know how you can argue that. Especially when its a larger driver, in a car, with alot of excursion. 
Here is a good link that explains the issue much better than I could. http://www.d-s-t.com.au/data/Peerless/Peerless_XLS_12_inch_subwoofer.pdf

The 1.4 cuft ported enclosure tuned to 25hz modeled on this page looks to be the clear winner, then again their not comparing it to a 15, I can see a 15 being 3db up at 25hz but who knows.

I run an Ava 18 ported to 18hz in my home and a Peerless xls 10 (sealed) in each of my vehicles, I like all kinds of enclosures.


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## Cruzer

i went from sealed to ported because there was no low end. very happy with ported low end tuned to 32hz. now i could probably go to a single sub to enjoy the low end SQ without the extra output ported provides


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## CorNut

+1 on ported 12


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## RyanM923

Wild Child said:


> At F3 and above (to a point) a ported enclosure will have more output, below F3 the sealed will have more output. Don't know how you can argue that.


Not true. That will only be the case if the f3 points are the same since a sealed box will have a shallower roll-off than a ported box. But f3's being the same is more often than not not going to be the case. When modeling woofers, you can easily get a f3 in the mid to upper 20's with a ported box and the right woofer, even 10-12" woofers. You will struggle to find any sealed setup that'll give you a f3 below 35hz, and if they can it's normally in a very large box that can be the same size or even bigger than a ported box of a different woofer that's the same size.

Most of the time when trying to decide between a ported or sealed setup, I model up the woofers I'm interested in getting, each preferring one alignment or the other. When I see that the sealed box won't be more efficient until the 15-20hz area, and that the ported box will have a good deal more output from 25-45hz, that pretty much makes up my mind since I'll never need to dig that low but still want the low-end spl where it matters in car audio.


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## Wheres The Butta

I think using a vented enclosure is a better option because it provides more flexibility. 

also because you'll get mad dbeeez


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## edouble101

Do the 15 with a 18 PR!!


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## tyroneshoes

Arc Audio/IDQ/TC epic 12 will work great in 2 cuft ported

Actually, an IDQ 15" tuned to 30 HZ will fit in there. Thats the one imo.


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## cleansoundz

Very good information.


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## DC/Hertz

sangellga said:


> I agree. If you are leaning more towards SQ go with the 15 sealed. Also, as I posted earlier, I hit 141.7 using 2 x 12s sealed and 1000 watts, and that was in a Ford Explorer SUV. Sealed can give decent SPL with the right driver and enclosure. Again 141 is not that high to an SPL chaser but it is FAR louder than needed for listening and more than adequate for those random volume demonstrations. Good Luck!


I would like to see this.


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## P-Med

Well, I was faced with the same decision and went with a dual ported 12" using the Infinity Reference 1260, tuned to 33Hz and I was not disappointed. The box is 60 litres net volume (just over 2 cuft), and the ports are 3" wide and 41cm long. (Sorry to mix metric and imperial.) I haven't measured dB SPL, but it's loud down to 30 Hz, and SQ is great.


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## Mark the Bold

I say go with a ported 12". I have a ported 10" Dayton HO" in a slightly oversized 0.9 cu.ft box tuned to 29Hz. Love it. Now, I'm not turning heads when I drive by (still gets plenty loud), but I listen to a lot of rock and I've nary heard a sub with a more natural sounding kick drum beat than my setup. CAVEAT: MS-8 helps me EQ big time.

Plus you DO have an SUV (jealous), the perfect canvas for subs to punch well above their weight.


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## Chaos

P-Med said:


> Well, I was faced with the same decision and went with a dual ported 12" using the Infinity Reference 1260, tuned to 33Hz and I was not disappointed. The box is 60 litres net volume (just over 2 cuft), and the ports are 3" wide and 41cm long. (Sorry to mix metric and imperial.) I haven't measured dB SPL, but it's loud down to 30 Hz, and SQ is great.



That's great, but why bump a 20 month old topic to post that?


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## P-Med

Because it's relatively informative, and it will come up in a Google search, and will help someone who's trying to decide between the two.

What is the point of your post?


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## Dave88LX

I found this through Google search!  I was looking at doing two 12s sealed; but was suggested another option of single ported 12. I don't know. More reading to do.


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## helpmeplease

It all depends on the driver.

A high end 12" can blow the doors off many 15"s.

if you are arguing the same company/model driver, only difference is the size of the cone and a few others, then it depends on the other parameters.

Can't just say "12 ported vs 15 sealed". 

But I wouldn't seal a 15".......

Why not just get 2 10's and seal them. They will save a lot of space and still have that SQ you're after.


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## rugdnit

Some of the comments on this thread are pretty funny and generally why the " which sub should I get " threads get little to no credibility. The JBL W15GTI is a superior driver compared to what the op offered up ( and many of what others have offered up ). With a properly built ported box there are 12's that have some great extension and sq, but I would take that 15GTI sealed all day long. There is some great info on this site regarding the JBL's -- perhaps the use of a search button and some reading is in order.


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## Spyke

*Sealed is not always for sq and ported is not always for spl!!!* You can get sq from sealed, ported, ib or whatever. I has to do with design and application.


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