Heres a picture of the SPL Graph. The sealed is really linear but lacks the output. The ported has a hugeee hump at tuning frequency, but even below or above tuning frequency, it has more output.

Green: Ported Dcon in 3.5cf box tuned to 33hz
Yellow: Sealed Dcon in 3.5cf box

 

Have you tried tuning a littler lower than hz to get rid of the hugeee hump?

 

My Kicker zx400 has an internal SSF at 25hz and by tuning it lower, Im losing output.

 

There's significant cabin gain in these trucks below 50hz. Just something I'd keep in mind.

 

How's the cone excursion at the peak?

 

It's not going to like peaking right there at around 30-35 hz, it's gonna distort.

 

What should I do to counteract that?
why do you say that?

 

Counteracting cabin gain is tricky, you can tune higher to help even it out but there's no absolute fix for it. Think of the truck as acting like a bigger box for the sub, and with the windows down it just becomes a huge ported box, so it'll peak even higher than what winisd shows because of it, it something that can't be factored in to programs like that.

As for my comment, because it's not built to be a low end monster sub. Peaking at the lower frequencies is going to be pushing the limit on the excursion of the sub which leads to distortion and eventually can damage the sub, it's like playing at full tilt all the time. It can be counteracted by keeping the gain cut back, however by doing that you'll lose a lot of output at upper frequencies. It's a give or take thing with ported boxes. If you know a song has a lot of bass in it you can cut down the volume to prevent it, but if that song has a lot of upper frequencies (>40hz) you'll lose output at those, because well the volume is cut back.

But not only is the excursion a limiting factor, but also the sub itself. It's made to be a optimal/affordable daily driving sub so in time, the peaking at those frequencies can lead to problems with the sub itself because it's not built for low end abuse.

 

Your Really pushing me towards a sealed box right now.

 

What kind of music do you mainly listen too? Answering that will tell you what box to build.

Bass heavy music = ported
Variety (rap, rock, country, etc.) = sealed.

 

I knew i was forgetting some info. I listen to mostly rap music but when some of my friends ride with me, they throw on some insane dubstep. Thats why i was leaning to ported because my sealed 10's cannot handle the lows well at all.

 

Then yea I'd go ported, but watch where the gain **** or volume **** is when you put that dubstep on. Those lows in those songs like less than about 26hz are really gonna be pushing the limits on that sub.

I would also try tuning a little lower because to help prevent unloading of the sub from when it rolls off that peak to hit those lower frequencies like you'll find in dubstep, maybe around 30hz.

 

Im also looking at the Digital Design 1000 series 15" sub. Ive heard good things about that brand and the price seems to be more accurate($175) than the $140 for the Dcon.

 

Definitely ported and a low tune if you listen to dubstep... I agree that the Dcon 15 doesn't model well in 3.5 ft^3 - it plots out better in a larger setup. No personal experience with Digital Designs, but they're geared more toward SPL.

Both the Dayton HO15 and Titanic MKIII work well in 3.5 tuned to 30hz. There's a hump between 30-40hz but it should sound fine with the music you like. The HO will be better for SQ but the Titanic will definitely be louder.

 

Just do this. Easier to design and build, less space, and with cabin gain you will have a much more linear response and better extension. Plus no stupid port noise in the cab. I personally think bass-heavy recordings sound terrible on a ported box (in vehicle, cabin gain) without the ability to EQ out the huge hump and tune for no port noise. But in the house, ported rules.

I have 2 sealed 12s under the seat in my truck to match the high powered front stage. I'm in the Sac area if you want to hear it.