5400 vs 5200 motor

[dgage]

Ok so I was trying to see how I could manage a port with such limited space.. I came to the conclusion that the only way I can get the correct cross area, and tuning I need to have two slot ports. One on each side of the front side of the box.. Is there any disadvantage to this?

Looks like a good idea to me. As an added benefit, you will have a very strong box. I'd recommend you double up the front baffle and you will have one heck of a strong subwoofer enclosure. Use round dowels between the inner and outer port walls to give some strength in the middle of those big panels and you should be golden.

 

[T3mpest 10+ year member]

There isn't enough depth to run both prs on the back, that would require 21.5"D and I only have 14.5 to work with.

Invert mount the sub?

 

[Bwap]

Invert mount the sub?

Cant do, would poke into the back of the back seat... or out the other side, I wouldn't have access to the spare..

How does the double port sound?.. it makes it so that I can have the length without hitting the back of the sub.

Heres a few examples of the response.. same as single port it seems. Any reason not to do this?

 

[T3mpest 10+ year member]

those ports are WAY undersized. You have less than 22^2 inches of port area. Most good 15's want around 45 square inches. The 5200 has far more motor force than almost anything else so it wants an even bigger port. If your really planned on powering this thing near it's 2k rms, you'd want around 75^2, so a 5inch port in your case. If you went on more power or wanted to burp, bigger wouldn't kill you. You will not be able to fit a port that is big enough for that woofer in a box the size that you have, it'll end up being too wide and interfering with the mounting, if it's long enough to be tuned anywhere you'd want.

We are back at what I already pointed out is the huge advantage to PR's. In a case of a supersub, you don't need to deal with the big ports. The passives I linked to have less than 6inches of mounting depth, however, you'd still have to get pretty creative to make it fit. Prhaps 3 12inch passives? If you ran one on the front with the sub and one on each side, I think you could fit it. The PSI radiators are over 8inches deep IIRC, so the ones I linked would be an easier fit. Either one you picked, you'd need 3 of them. Keep the sub and the one passive in the "center" of the box so you can use the box width as your depth, since they'd be side firing. You'd still want to seal your trunk off, but mostly from the back this time, to keep the side passives firing "forward" so to speak.

The other easy option, if you really want to run a 5200, you could do it sealed for right now. After that if you want to go ported, go down to a 12 and do a 12 with a pair of 12 inch PR's. That sub has plenty of excursion and needs **** all for box space sealed. Throw it in a box around 2 cubic feet and call it a day, you can even go as small as 1.5cubes with virtually no change, or as big as you want, no change. Your giving up 3db's at 30hz, not the biggest loss ever and it actually will easily fit. Your not fitting a port into this thing so if a passive on each side and a passive on the same face as the sub doesn't work, you need to just go sealed if you want that 5200.

 

[gckless 5,000+ posts]

So, with PR's what you're concerned with is Vd. Rule of thumb is double the Vd in the PRs as you have in the powered drivers, and while you can get away with less, you don't want less. This is even more important when you're talking more power or lower tuning. I currently have 1.6 times the Vd in my passives, and it's not enough. I reach mechanical limits if I'm full tilt at or under my tuning, which is where your passives are going to move the most. I'm also running 4k, so that makes it worse. It's a balance in tuning also because to tune lower you need to add more weight, and if you have more weight there's more for the suspension to control, which can only do so much with that much weight. It's a delicate balance for me, I should have done more PR. There is a point of diminishing returns, maybe 3-3.5 times the Vd or more (though that's not something I tested), but up to that the more PR you can get the better.

As for orientation, probably the best you can do, depending on vehicle, is sub up or back and PR's on left and right sides. That way the movement of each PR cancels itself out. When those things get really moving, your whole box is going to move. I know mine does, and it's built pretty solid.

Sorry if I repeated anyone, didn't read much in the middle, but I seen some smart dudes in the thread.