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82 cutlass
03-11-2012, 07:07 PM
I'm about to do a 4th order through the rear deck of my town car . 2 sundown sa 15's . How much port do you guy's think would be a good start ? Box is going to be 4 cubes sealed...8 ported tuned to 48hz. on 1500 watts . I'm thinking around 120-140 inches of port . Or should I go with more being on 1500 watts ?

Thanks for any help

RangerDangerV2
03-11-2012, 07:11 PM
180-200

galacticmonkey
03-11-2012, 07:32 PM
What are your goals?

You dont want anywhere near 200in^ of port. And 8 cubes ported isnt necessary.

Kangaroux
03-11-2012, 07:35 PM
I would stick with 120-140 on the port. Too much and it might be a bit too peaky for your liking

RAM_Designs
03-11-2012, 10:58 PM
Yeah, 200in^2 is way too big. Usually if you stay around 1/3-1/2 of the woofer's sd, then you're good. In this case, that would be about 100-125in^2 or port area.

NutHugger
03-11-2012, 11:36 PM
another ecellent designer as far as i can tell

yah bro he is i asked him some questions and he got me lined out quick. told me 4 cuft tuning 32. im gonna go get some chip bord and nails tomorrow and build my first ram designs box!

KRYPTO
03-12-2012, 08:29 PM
I'm looking at doing a 6th or 8th order in my town car, any inputs?

82 cutlass
03-14-2012, 12:44 AM
What are your goals?

You dont want anywhere near 200in^ of port. And 8 cubes ported isnt necessary.

Loud and low...daily pounder . I'm thinking like 4 sealed and 6 ported tuned to around 48-50 hz. With like 120 in. of port to start . I'll build it so I can change the port if necessary .

82 cutlass
03-14-2012, 12:48 AM
Yeah, 200in^2 is way too big. Usually if you stay around 1/3-1/2 of the woofer's sd, then you're good. In this case, that would be about 100-125in^2 or port area.

I was thinking around 120in^2 to start . How's 4 sealed and 6 ported tuned around 48-50 hz. ?

Thanks for the help guys

Moble Enclosurs
03-14-2012, 01:00 AM
You can just throw numbers out and expect superior results. but what i recommend in this case is to listen to McCabe had to say. Same drivers and he went through quite a bit of changing before something was desirable. That kind of experience is fully necessary when dealing with bandpasses rather than throwing out numbers and going with a generic 2:1 ratio.

But for informational purposes, 200sqin can work well if the design allows it to. But the room needed may be quite large. Not to say that certain more complex designs can be scaled but i would not recommend using just a numbered recommendation with the full understanding of the design as a whole.

The great thing about 4th orders, is phase control can be less important than in a combined phase design idea, so generally, if you want to stick with just numbers for designing a forth, it will work......just might not be what you want in the end.
Either way, good luck on the build and i hope it works for you! Keep us updated!
By using a designer, you will get much better results than just, "try this.....".

82 cutlass
03-14-2012, 01:01 AM
i dont have near that amount of ported area, but my trunk isnt quite as big as yours either. i went with 100sqinch of port throiugh myvery knoledagble rear armrest, and im happy with it. 1500 watts on 2 sa 15s. 120 would be probubly close to where u need to be, stay within what ever gmonkey has for u on his advice. worked really well for me, and noone else seems to know quite as much about actual results for a 4th order, they just have the programs and software capabilities, which is ok , but for actual results gmonkey seemed to be most helpful


Can u smellllllllllll, what the rock is cookin?!!!

Seen your video's on youtube...nice job . How's it sound now after you made the port bigger ?

SourDeez
03-14-2012, 01:04 AM
I need to do this in my grand marquis...

82 cutlass
03-14-2012, 01:07 AM
You can just throw numbers out and expect superior results. but what i recommend in this case is to listen to McCabe had to say. Same drivers and he went through quite a bit of changing before something was desirable. That kind of experience is fully necessary when dealing with bandpasses rather than throwing out numbers and going with a generic 2:1 ratio.

But for informational purposes, 200sqin can work well if the design allows it to. But the room needed may be quite large. Not to say that certain more complex designs can be scaled but i would not recommend using just a numbered recommendation with the full understanding of the design as a whole.



The great thing about 4th orders, is phase control can be less important than in a combined phase design idea, so generally, if you want to stick with just numbers for designing a forth, it will work......just might not be what you want in the end.
Either way, good luck on the build and i hope it works for you! Keep us updated!
By using a designer, you will get much better results than just, "try this.....".

Thanks...Yeah I hear ya...don't know till you build it . Build and maybe build again to get the results

82 cutlass
03-14-2012, 01:09 AM
I need to do this in my grand marquis...

Do it up...

SourDeez
03-14-2012, 02:07 AM
Do it up...

Not sure where to start.. maybe I should just crash it into a dairy queen then buy a tahoe

82 cutlass
03-14-2012, 02:14 AM
lol

galacticmonkey
03-15-2012, 05:43 PM
Loud and low...daily pounder . I'm thinking like 4 sealed and 6 ported tuned to around 48-50 hz. With like 120 in. of port to start . I'll build it so I can change the port if necessary .

Btw, Im the one on FLSPL who gave you the recommendations for 4 sealed/6 ported. My name is Chuck on there.

82 cutlass
03-16-2012, 11:55 PM
Btw, Im the one on FLSPL who gave you the recommendations for 4 sealed/6 ported. My name is Chuck on there.

Yes.. I know

Thanks man