Loudest SPL/SQL sealed set up

[akuma4u]

ok so it rolls off below tuning frequency, what about above? same thing? and ya im looking for as flat as possible so i can play a wide variety of bass frequencies LOUD. But at the same time i got around a 2.25 cube limit so the box cant get too big. I guess this is where sealed boxes excel because they can maintain a small size while having a flat response with the exception of being able to play really low

hmmm.. i was thinking it was the other way around, i thought they all tuned their boxes really low and then i played something with bass in the 40s and it ended up sounding weak.

Theres no way i can have a 12 inch sub facing rear or towards me, it can only be facing UP. because the max height i can get into the trunk is 11inches. So i guess sub up port back would be best. ive deadened my whole lid and spray foamed it so ive taken care of the rattling.. that made a huge difference.

With a properly designed ported box there is no roll off above tuning, at least not until you get to where the sub is going to roll off no matter what (like 200 Hz). Obviously not all ported boxes sound this way, but if that is what you want it certainly can be done.

Generally speaking, if you are looking for a smoother response curve you are going to want a smaller box that is lower tuned. You are also going to have to pick a sub that naturally has a flatter response, there are plenty to choose from.

ok so if there is no roll off above tuning then that means i should tune the box as low as possible. its better to tune it to 30hz and maintain all the frequencies above that rather than tune it at 42hz and lose the frequencies below that.

well the subs i was looking at , i have no idea what kind of response they have and dont even know how to find that info..

heres a list of subs im interested in (and i can also do the 10 inch versions of these as well)

dd 712

dd ts 3512

dc lvl 4

dc lvl3

AA havok

sundown zv3

sundown sa12/sa10

any of those subs have a flat response?

[bigsausagepizza]

Wait until you see what happens to the port length with a small-ish box when you keep lowering tuning and try to maintain enough port area....

[Triticum Agricolam]

ok so if there is no roll off above tuning then that means i should tune the box as low as possible. its better to tune it to 30hz and maintain all the frequencies above that rather than tune it at 42hz and lose the frequencies below that.

well the subs i was looking at , i have no idea what kind of response they have and dont even know how to find that info..

heres a list of subs im interested in (and i can also do the 10 inch versions of these as well)

dd 712

dd ts 3512

dc lvl 4

dc lvl3

AA havok

sundown zv3

sundown sa12/sa10

any of those subs have a flat response?

WinISD can tell you want kind of response to expect. You can download it here: http://www.linearteam.org/download/winisd-07x.exe

I might be able to model some of those subs in WinISD for you later tonight.

Wait until you see what happens to the port length with a small-ish box when you keep lowering tuning and try to maintain enough port area....

Lol, that is always the problem. At least the OP is looking at a 15" sub instead of a 8" or 10". Its a LOT tougher with those small subs and the small boxes they need.

[akuma4u]

ok so if there is no roll off above tuning then that means i should tune the box as low as possible. its better to tune it to 30hz and maintain all the frequencies above that rather than tune it at 42hz and lose the frequencies below that.

well the subs i was looking at , i have no idea what kind of response they have and dont even know how to find that info..

heres a list of subs im interested in (and i can also do the 10 inch versions of these as well)

dd 712

dd ts 3512

dc lvl 4

dc lvl3

AA havok

sundown zv3

sundown sa12/sa10

any of those subs have a flat response?

WinISD can tell you want kind of response to expect. You can download it here: http://www.linearteam.org/download/winisd-07x.exe

I might be able to model some of those subs in WinISD for you later tonight.

Great thanks please do that as i have no idea how to use winisd or what it even is, im assuming its a graph that compared the output of subwoofers.. how accurate is it though?

[Triticum Agricolam]

Out of all the subs you listed the SA-12 looks the best to me. Here is an example of what I'm talking about:

The red line is the DD TS3512, the green line is the SA-12. You can see the DD sub has a much more pronounced peak. When you add in the cabin gain you will be getting you end up with a big peak. Actually the SA-12 is still fairly peaky by my standards, but it was the best looking of the bunch. You can reduce the peakyness by keeping the box size small, which it sounds like is something you want to do anyway, and by tuning low.

[akuma4u]

Out of all the subs you listed the SA-12 looks the best to me. Here is an example of what I'm talking about:

The red line is the DD TS3512, the green line is the SA-12. You can see the DD sub has a much more pronounced peak. When you add in the cabin gain you will be getting you end up with a big peak. Actually the SA-12 is still fairly peaky by my standards, but it was the best looking of the bunch. You can reduce the peakyness by keeping the box size small, which it sounds like is something you want to do anyway, and by tuning low.

hey man thanks for doing that for me. Now, pardon my noobness but is this graph comparing one 12 to one 12 ported vs ported?

and it seems the TS is "peaky" right in all the good frequencies 28-50hz, those frequencies is where almost all genres of music have their basslines. The SA is more flat throughout all frequencies. So umm.. wouldnt peaky be better then in this case as it would be harder hitting and louder? or is the SAs flatter response better?

Im looking for something that hits HARD like every bass drop that hits i want it to feel like you are being punched in the head.

Also i heard the SAs require a huge box - i was actually told that today by a guy at a shop who told me the JL w7 10s would be better than the SAs..

Would i be able to run 2 SA-12s or 2 SA 10s in a 2.25-2.50 cube box? and im assuming SAs only run well in ported set ups?

thanks for your help

[Triticum Agricolam]

Both the subs in the graph I showed you were single 12"s in a 2.25 net cubic foot box tuned to 32 Hz.

I agree that the TS3512 graph does look better with its slight boost in the 30-40 hz range, the problem is cabin gain. Cabin gain is going to turn that slight boost into a giant peak. Let me show you:

This graph shows the same two subs with the approximated cabin gain you are going to get in an average SUV. Its just a rough estimate of cabin gain, but it shows you what happens. The TS3512 (red line) now has a big peak in output in the low 30's and falls off quickly above and below that, its going to be a one-note wonder. The SA-12 (green line) is still pretty peaky, but not as bad. The yellow line is the kind of response I like to shoot for with the boxes I build (its a FI SSD 15 in a 2.75 cu ft box tuned to 32 Hz BTW). I like a gradually rising response of 8-10 db. Now just because that's what I like doesn't mean that's what you will like too. There really is not right or wrong here, its just a matter of personal tastes. I just wanted to show you this so you can see the difference between what different subs will do in different boxes.

For comparison purposes here is a SA-12 in a 1.2 cube sealed box w/ approximated cabin gain (blue line):

The SA-12 performs just fine in a sealed box, this graphs illustrates why ported boxes generally have a lot more low end punch than sealed boxes do.

[akuma4u]

Both the subs in the graph I showed you were single 12"s in a 2.25 net cubic foot box tuned to 32 Hz.

I agree that the TS3512 graph does look better with its slight boost in the 30-40 hz range, the problem is cabin gain. Cabin gain is going to turn that slight boost into a giant peak. Let me show you:

This graph shows the same two subs with the approximated cabin gain you are going to get in an average SUV. Its just a rough estimate of cabin gain, but it shows you what happens. The TS3512 (red line) now has a big peak in output in the low 30's and falls off quickly above and below that, its going to be a one-note wonder. The SA-12 (green line) is still pretty peaky, but not as bad. The yellow line is the kind of response I like to shoot for with the boxes I build (its a FI SSD 15 in a 2.75 cu ft box tuned to 32 Hz BTW). I like a gradually rising response of 8-10 db. Now just because that's what I like doesn't mean that's what you will like too. There really is not right or wrong here, its just a matter of personal tastes. I just wanted to show you this so you can see the difference between what different subs will do in different boxes.

For comparison purposes here is a SA-12 in a 1.2 cube sealed box w/ approximated cabin gain (blue line):

The SA-12 performs just fine in a sealed box, this graphs illustrates why ported boxes generally have a lot more low end punch than sealed boxes do.

hey its starting to become more clear now.. i have a small coupe so the cabin gain is going to be much MUCH less than an SUV so how would that change the curve on the ported SA and TS? would it still make them peakyish in the low to mid 30s?

the sealed SA is a good 8db less than a ported sa, thats a huge difference!

what subs do u recommend other than the fi ssd to give that nice flat response curve.. or did all your research conclude that the fi ssd was the best sub to achieve that?

wish we lived closer, would love to get u to make me a box man.. unless u are cool with shipping it or meeting me close to the border..

[Inetba]

I can understand your confusion OP so I will explain the technical jargon.

Some songs have bass lines at 60-80hz. For this example we will say song A. Some songs have bass at 40hz. Song B. Some songs have mixed bass between 40-80hz. Song C. Let's set the head unit to 20/35 on the volume knob and bass boost is set to +15.

With the digital design subwoofer, Song A will sound fine, song B will be WAY TOO LOUD and song C you will have to spend the entire song alternating between turning the music up and down or else the song will jump between louder than a shotgun and quieter than your door speakers.

With the SA subwoofer in a sealed box, Song A, B, and C will all pretty much be equal in loudness. Either all three songs are quieter than your doors of all three songs are louder than a rock concert. You set the equalizer once and you don't have to worry about it being too loud and you don't have to worry about any surprises.

How do I know all this? I have a VERY peaky box. A Millie (48hz) I have to set the bass to -15 and it STILL rattles my doors with dampening and the head unit set to 12/35. On the other hand, 24 hz, I can listen to that with the bass cranked up as high as it can possibly go and still be sitting comfortable.

Ultimately, the 12" digital design in a ported box will be the loudest on ALL frequencies, but you will have to deal with it being TOO LOUD on some songs and having to crank the bass on other songs, while the SA in a sealed box you can just crank the bass and not worry about it again.

[Triticum Agricolam]

hey its starting to become more clear now.. i have a small coupe so the cabin gain is going to be much MUCH less than an SUV so how would that change the curve on the ported SA and TS? would it still make them peakyish in the low to mid 30s?

the sealed SA is a good 8db less than a ported sa, thats a huge difference!

what subs do u recommend other than the fi ssd to give that nice flat response curve.. or did all your research conclude that the fi ssd was the best sub to achieve that?

wish we lived closer, would love to get u to make me a box man.. unless u are cool with shipping it or meeting me close to the border..

You are right about your small car, it will probably have even more cabin gain, which will make any sub sound more peaky.

I wasn't really trying to recommend the SSD 15 to you (though it is a great choice), I was just showing it for comparison purposes. Its really up to you to decide what you think would be best. I'm just trying to show you how to get the information you need to make that decision.

What Inetba said about how peaky bass sounds really hit the nail on the head. Having peaky bass will mostly likely result in having an overall louder system, but you are going to have to be all over that bass knob turning things up and down on every single song, depending on just how peaky your system ends up being. I used to have a system like that and I didn't like it. I like to set it and forget it as much as possible.

I still think a single 12" in a ported box is probably going to be the way to go for what you want to do, you just need to find the right combination of sub and box specs to give you what you want to have.