I want to build a folded horn box. (they are just like a ported box, but the ports are made with MDF instead of plastic.) I just wanted to know if anyone had any info on the specs of how to build one? and how big to make the "folded horn" port?
Folded horns are not "just like" a ported design. They are very different, and very difficult to make sound musical.
HERE's one I built once. I ended up disassembling it as I was not happy with the results...
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Support the12volt.com Here you go free plans,all the math done.Be careful what you put in them they are deadly efficient boxes.they tune very low.
https://www.decware.com/newsite/mainmenu.htm
i'm guessing that you want to get an insane amount of output correct?
a horn is not the way to do it. a horn is designed to be a long throw device( sound 100% better from far away) that is why you typicaly see them in big venues such as concerts,raves,etc. these do not sound good in a car or a home period.
if you want extreme output look into other box designs. here are a few suggestions
Transmission line: extremely hard to design and build but gets good output and awsome sound quality.
voight pipe: similar to the t-line but easier to design and build and has increased output with decreased SQ (kickers solobaric slot ported box is very close to what a voight pipe looks like)
servo driven: EXPENSIVE!!!! basicaly a speaker that is driven by a servo motor extremely efficient i had one that i used in my DJ rig. its specs said it was 102 db at 1 watt/1 meter. with max input of only 200 watts i was shacking glasses off the bar and flexing double pane windows about 5 inches.
ELF (extended low frequency: this is very space efficient but requires a special type of dsp that isnt available very cheap but can be built for about $65. the dsp basically evens out response below resonence. so instead of your sub dropping at 12 db per octive below resonence it will actually play flat below resonence. the cool thing about it is that propper design actually calls for a pretty small box. i first saw this box at the national association of music merchants show made by a company called Bag End . the rep was fanning paper in front of a mic and the speaker was responding to it by moving in and out at the same pace. thats extremely low output.
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";P
I am just assuming you are trying to build a slot port box, the port vary's depending on the subs, you will have to tell us the subs =being used for help with a box design
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2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place
they are two JL 12w0.
So what's the answer to the question: are you really thinking about a folded horn cabinet or are you talking about a slot-port design?
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Support the12volt.comIf you are looking at a slot port design I would actually go with a common chamber slot port..I typicvally use this for 10wo's and have gotten 2 to acchive 136db, I would go with a common chamber measuring about 2.8 cu ft internal which would give you a port of roughly 1.5x28.5x20 I would run the port across the bottom of the box from one side to the other. we have had great results with boxes designed like this for w0 and w3 subs...let me know if you need any additional help
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2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place