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BobbyDD
09-07-2007, 12:00 AM
I'm embarrassed to have to ask this, but I've been reading here and following links for hours trying to figure this out but I'm not getting it. I came across a used enclosure and I need to see what it's tuned to so I can decide on subs to put in it. All dimensions are interior dimensions. Width 46.5, height 14.5, Top depth 5.5, Bottom depth 12.5. It's for two 12s with subs back and port up. Interior slot port dimensions are 19x12.5x1.75. I'm thinking it'll be about 3.75 cubic feet after displacement but I'm not sure about that either. Can someone please tell me what it's tuned to? Also if you can plug these numbers into whatever formula you use and post it here I'd appreciate it so I can learn how to do it. If you need more info just ask. Thanks.

BobbyDD
09-07-2007, 04:32 PM
Anybody able to help, please??

billabongcr
09-07-2007, 04:34 PM
reaudio.com box design program

toward the bottom of the first page

BobbyDD
09-07-2007, 10:46 PM
reaudio.com box design program

toward the bottom of the first page

Thanks. I tried that but I can't get it to accept my port dimensions. My port's on top 14.5 inches wide centered on the box. It goes down and then turns toward the back of the box for a total of 19 inches long. It's only 1.75 inches deep. Any help is appreciated.

IamDeMan
09-08-2007, 08:15 AM
Thanks. I tried that but I can't get it to accept my port dimensions. My port's on top 14.5 inches wide centered on the box. It goes down and then turns toward the back of the box for a total of 19 inches long. It's only 1.75 inches deep. Any help is appreciated.In your original post you said it was 12.5".

If it is 14.5" then I get a tuning somehwere in the neighborhood of 28hz. Your net volume after port displacement seems correct at 3.75

BobbyDD
09-08-2007, 09:02 AM
In your original post you said it was 12.5".

If it is 14.5" then I get a tuning somehwere in the neighborhood of 28hz. Your net volume after port displacement seems correct at 3.75

Dang, you're right. I accidentally copied the bottom depth down for one of the port measurements. Thanks a lot. Do you have any suggestions on 2 12" subs that would work well in this box with a kx2500 on them? It looks to be a perfect match for the RL-p. The Q seems to work too but it's on the small end of their ported box recommendations. Any suggestions? Thanks again iamdeman.

azbass
09-08-2007, 09:03 AM
41.9256 1/2 hertz

BobbyDD
09-08-2007, 09:15 AM
41.9256 1/2 hertz

Is that using the 12.5 inch port measurement I posted incorrectly or the 14.5 inch measurement?

IamDeMan
09-08-2007, 10:58 AM
41.9256 1/2 hertz
???? I know winisd isn't off by that much. I am going back to check this again, that doesnt sound right at all.

IamDeMan
09-08-2007, 11:10 AM
I still get between 28-29. AZ are you factoring both depths or just the first one? If I use the 5.5 as the only depth then yes I get >40hz.

IamDeMan
09-08-2007, 11:13 AM
Dang, you're right. I accidentally copied the bottom depth down for one of the port measurements. Thanks a lot. Do you have any suggestions on 2 12" subs that would work well in this box with a kx2500 on them? It looks to be a perfect match for the RL-p. The Q seems to work too but it's on the small end of their ported box recommendations. Any suggestions? Thanks again iamdeman.
The volume is a bit small for most modern high excursion 12" drivers. Maybe make a new baffle for 1X 15". But then you run into the port being too small of area.

dB-SPL
09-08-2007, 12:10 PM
The volume is a bit small for most modern high excursion 12" drivers. Maybe make a new baffle for 1X 15". But then you run into the port being too small of area.

If it's too small for most of todays 12" competition drivers, can't he just make a baffle for two nice 10's and just screw/glue additional pieces of wood to the inside of the port to compensate?

IamDeMan
09-08-2007, 02:39 PM
If it's too small for most of todays 12" competition drivers, can't he just make a baffle for two nice 10's and just screw/glue additional pieces of wood to the inside of the port to compensate?Yes 2 nice 10s would work too. Just make a new baffle to glue and screw to the original.

BobbyDD
09-09-2007, 12:08 AM
You don't think RL-ps would work well if it is indeed tuned to 28? These are the recommendations from their site.

Optimal Car:
1.35 cu ft net volume sealed
1.5 cu ft net volume vented, Fb = 34 Hz
1.85 cu ft net volume vented, Fb = 28 Hz

I already have a 15" HD3 now in a 4 cubic foot, 40 hz box from Woodlawn Cabinetry, so I don't need another box for that. I don't really wanna spend a bunch of money on subs if it's not gonna be louder than what I have now.

Does anyone else wanna chime in on the tuning? It makes a big difference in what subs I get if any. Thanks to everyone that helped me so far.

IamDeMan
09-09-2007, 08:49 AM
You don't think RL-ps would work well if it is indeed tuned to 28? These are the recommendations from their site.


I already have a 15" HD3 now in a 4 cubic foot, 40 hz box from Woodlawn Cabinetry, so I don't need another box for that. I don't really wanna spend a bunch of money on subs if it's not gonna be louder than what I have now.

Does anyone else wanna chime in on the tuning? It makes a big difference in what subs I get if any. Thanks to everyone that helped me so far.
I wasn't familiar with RLP and didn't realize their recomended ported was so small. I thought mag with 2@32 was the 12" with the smallest volume recomendation. In any event that port area is too small for 2X 12" IMO. You are gonna get some port noise with only 25 sqin. I can tell you it definitely won't be louder than what you have now with any 2 12" drivers. This box is tuned for a flat response. You will have a better sounding setup with a lower response(dependng on which driver is chosen) but I doubt it will be louder.

BobbyDD
09-09-2007, 10:33 PM
Thanks for the help man.