Folded horn hybrid

login4 wrote: hi guys, this has been an interesting read and quite exiting, because as i have said before there are loads of these ported horns out in thailand and they realy do sound great, i did notice that the throw and sheer horn spl wasn't as much as a standard horn loaded bin but it was realy warm bass and dropped realy low, the only design that iv found these even resembles what i heard out there was this: and it does look like there might be some sort of tapped bit there with the 10L section on the horn...

you need to go and hear 8 or 12 XXL's

i told you in a post ages ago about those 2 x 18 EAW cabs, the one where the drivers are on an angle to each other, quite deep cabs

it will look very similar, but so much better

I once built this chipboard cab, started life as a straight horn, my llittle bro wanted to take it to a party so we sawed it in half folded it up and made up a new rear chamber with offcuts, didn't sound to bad, he reckoned it floored a pair of Bose 302 bins at the party.
Had to be destroyed to get the 15XB driver out as it was sealed into the cabinet.

http://i215.photobucket.com/albums/cc107/Subsoniks/ChipboardBodge2.jpg

JaKe

For a prototype I would be tempted to make the rear chamber about 50% larger than in your calculations to give you some room for tuning, you can then change the volume with bricks etc.
In my design the port  throat is loaded by the volume of air in the horn so that needs taking into account when calculating the port size.
The design you have posted also resembles a series tuned bandpass enclosure if you tune the port onto the throat.

JaKe

JaKe wrote: In my design the port  throat is loaded by the volume of air in the horn so that needs taking into account when calculating the port size.

Sorry to keep picking at your brains Jake... this is what I can't get my head round..how do I model with this taken into acount...by modelling the port as the horn throat and rear chamber as front chamber of a front load horn??? This obviously produces a plot with a peak higher uip the range due to small "throat" (port)  size.
The main problem is that I am trying to apply this concept further up the range..I can see (and make sense of) the large port area in your design which will lower cut off for the horn element.. in a design tuned for low mid frequency this is harder to balance out.

more like an X1. but with rounded rear ports