Im broke because of this build.

[rival904 10+ year member]

The guy who designed Desires box, is the same guy who designed this box, and is the same guy that DD goes through for ALL of their demo vehicles.

I think HE would know the best, if anyone on what these subs should do in this setup, also, a smaller sealed/porter chamber will allow me to run more power, considering I will be running twice the RMS power to these subs, power handling was important.

Heres what he said when I asked him about the small sealed/ported ratio and the small cu.in of port

"Dude, I'm getting so tired of this. It's not you, it's just the whole idea of me busting my *** as hard as I do with all the R&D, the particle collision engine, resistive transfer theory, etc., only to be second-guessed by some kid that treats a complex cabin / enclosure model like a children's coloring book. I mean, sealed and ported volumes? I honestly thought you were just being cute by mimicking those challenged WinISD jockeys on CA.com. I'd be interested to know how the person giving you advice is compensating for reactive cabin impedance acting on the port (or the effect that this has on the center chamber's equivalent air mass capacitance.) On the other hand, that's pointless; asking questions that you know someone isn't going to have the answers to is like quizzing a creationist on the theory of evolution--you're not proving anything and you **** sure aren't teaching them anything; it's like a special Olympics pissing match. All right... End of rant."

And then he said

"It’s all good. We’ll let the box speak for itself once it’s built and playing. I’m just a bit *****y because I’ve been up for the past 48 hours. (That, and Thumper from the forum pulled the exact same shit a little while back when he got his design; came back talking about sealed and ported volumes adding up to something weird looking when modeled on a toy like WinISD, BassBox Pro, or some online box calculator…) Well anyway. I hope you like the way your setup sounds. Make ABSOLUTELY CERTAIN that you have no air leaks. And, if you’d like, you can put in additional bracing in the center chamber (iron rods, 2x4s, etc…) Best of luck."

Him and DD are obviously doing something right with their current track record.

 

[STR8BLaZiNTB 10+ year member]

k.

I'm waiting on Highs on Bass's response. lol.. just noticed this build and I must say.. are there more pics?!?!

 

[Highs on bass]

sure. but 1.7 cubes ported for a 15 with only about 31.5 square inches. and from my experience from building boxes, as well as doing this same thing. smaller box smaller port more power in my last setup, IT DOESN"T Work like your thinking.TRUST ME i've done it.

 

[Highs on bass]

and yes, the port is way too small. just look at the van you keep refering too. there are kids an guys sitting/standing in their port.... your port is way!!! to small!!!! this is just destined to fail, and fail HARD.

BUT I hope i'm wrong! 8 15's on gobs of power are going to be loud sealed. but with a better sized box you will see a lot better result. and I believe just about any box builder, or anyone who expects anything out of a decent system will tell you the same thing. but also I didn't ask I just assumed this is a daily. because your setup is gonna be only good as a fart box with that size port.

 

[Highs on bass]

again I hope i'm wrong. But I just finished a build with a smaller box with smaller port, with more power, and it sucked. not the same equipment, no but its easy to compare the output capabilities of the setup because i've used my same equipment in different sized setups and see the potential. honestly with that box specs you be better off doing 4 maybe 5 of those 15's at best, not 8

 

[Highs on bass]

^^^ my 2 cents. your ports too small, and the ported side is too small. I think you are going to have way too much load pressure inside that thing and your gonna have some serious issues with your subs being capable of actually getting their excursion out. I think your just going to eat up some subs.

or your going to need to rebuild this with alot more port and or airspace. the airspace isn't so much the issue, just the port is going to kill this setup. way too small.

 

[galacticmonkey 5,000+ posts]

Hes saying the same thing Im saying. That in a bandpass, all the sound comes through the port, so if the port is small, the sound is small. That the airspace that pressurizes the port is important as well. 8 15s wont push x amount of air in the ported chamber. They will excite however much air is in the ported chambed. If the ported chamber were say 40 cubes, they would excite 40 cubes worth of air. Then that 40 cubic feet of air will excite the air in the port, which will create the sound. Small ported chamber and small port = small amount of air moving. Big ported chamber and big port = big amount of air moving.

Getting loud is all about exciting air, and when youre choking off the size of the ported chamber and the port you are losing all chance of efficiency.

Looking at the vids, the Desiard Pawn van has a hugeeee port like my van did and a pretty big ported chamber. The port in that van is probably around 1,000in^.

Im really hoping this does work out in the end though.

 

[Highs on bass]

Hes saying the same thing Im saying. That in a bandpass, all the sound comes through the port, so if the port is small, the sound is small. That the airspace that pressurizes the port is important as well. 8 15s wont push x amount of air in the ported chamber. They will excite however much air is in the ported chambed. If the ported chamber were say 40 cubes, they would excite 40 cubes worth of air. Then that 40 cubic feet of air will excite the air in the port, which will create the sound. Small ported chamber and small port = small amount of air moving. Big ported chamber and big port = big amount of air moving.
Getting loud is all about exciting air, and when youre choking off the size of the ported chamber and the port you are losing all chance of efficiency.

Looking at the vids, the Desiard Pawn van has a hugeeee port like my van did and a pretty big ported chamber. The port in that van is probably around 1,000in^.

Im really hoping this does work out in the end though.

exactly what i've been saying.

Again I hope you prove me wrong, but that port is way to small. its going to fail.

unless they were some funky pups //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[galacticmonkey 5,000+ posts]

Even if he had Xplods, the port velocity would still be very high. It doesnt matter what subs are in there, what matters is the ratio of port area to ported airspace. Its not that the subs directly blow air out of the port, its that the air in the ported airspace gets "excited" and moves out of the port.

Bigger ported chamber = more air being excited.

More air being excited = more air being moved through the port.

More air being moved into the cabin = louder.

 

[Highs on bass]

hmmm... waiting for OP to chime in with a response to this ... betting its nuhh uhhh its gonna be great. that none of your opinions are close to being correct

 

[Annnarbor84 5,000+ posts]

I know Pete is designing for DD, is that who you got these plans from?

 

[Highs on bass]

he said that the same guy who designed the box for the st pawn van is the guy who designed this box. apparently its close to the specs on this box as well. but anyone who would say that the port size on this box is ok, well i'd question his understanding of box design lol.

 

[Annnarbor84 5,000+ posts]

he said that the same guy who designed the box for the st pawn van is the guy who designed this box. apparently its close to the specs on this box as well. but anyone who would say that the port size on this box is ok, well i'd question his understanding of box design lol.

If Pete designed this box, then you would be a fool for second guessing him. That guy is a genius, it has been proven time and time again:thumbupw:

 

[Highs on bass]

I don't doubt the guy who did the stuff for DD so "Pete". But I don't think that Pete would have a port this small on a box that houses 8 15 inch subs. It is just counter productive.

 

[corona_jeff 10+ year member]

Well I think you both have valid points, but 2 things you guys are leaving out. Pete knows his shit, and DD subs are like no other sub. Im not saying they are better, just that most general things that others uses dont work with these. I think you all will be suprise.d NOW GET THE THING DONE