hi,  this is my first post.  I've pondered these designs for ages and after recommendation thought it about time I build a WO.

I've measured out a 36 x 24 wo for 12" drivers.  the rear chamber seems as though its gonna be a pretty tight squeeze  with a limited volume in comparison to some of the pics i've browsed on the forum .

has anyone else built a 36 x 24 12" with some decent success?

OR.....Go for the gusto and build a 12X36X36, you'll be glad you did.

hi, thanks for the replys.  The reason for the small box is limited space, and the reason for the 12"'s is the limited number of 10's with a decent spec.
I wanna stay away from car drivers and go pro audio, I've read nearly every post on the forum twice but cant find anywhere a recommended driver parameter list.  Is there one kicking about anywhere.

hi,  its mainly for the back of my vw t4 day van.  but I also want to be able to pull it out when we go off into the middle of nowhere for little partys.
If I like the design I was going to make  some of the bigger version to play sub under my kick bins for PA use.

Cheers for the link to the drivers, I'm in the Uk so postage will prob be a bit much.  I'll see if I can find a 10" driver with a similar spec over here.

One last thing, when it comes to modeling the rear chamber how do I go about it in winisd?  I've only ever designed ported boxes in it.

I opened a 4th order bandpass design but wasnt sure what to set the tuning port size/length and front chamber too so that I could work out the rear chamber.

If I was going to use a bigger driver like the 12 I would match the driver volume up and shrink the compression chamber/ increase the sealed chamber.
just slide the baffle board. The WO is pretty forgiving but don't go to far if you need more sealed volume.
You could add polyester fill to the sealed area but don't pack it. accustic fiberglass is suppossed to be better.
If your driver is flipped so it faces into the sealed area I use fiberglass screening to keep it away from the the driver.


have fun and good luck..
by the way Zygi is part of the Decware team.

EDIT: post edited because of lack of intelligence and sleep

My bad!
Previous post EDITED

Thanks Adrian.
Trying to remember what I was thinking at the time. I think I was remembering an article I read on the simularities of the Horn and the ported box on the driver.

I had something else on my mind.. and I was trying to do two things as once..
Must have been a acid flashback from the early 70's

The WO is a simply a 4th order bandpass enclosure with a modified mouth.

i've just found car drivers to be a bit boom boom in the past. and their sensitivity is alway way down on PA drivers.  Maybe I should just give some a try.

What does reducing the compression chamber do to the characteristics of  the box?

Also i'm still unsure of how to model a 4th order BP for a WO in Winisd pro.  If anyone can give me an idiots guide i'd be greatful.

[quote author=60ndown  link=1145737888/0#11 date=1145799871]

i dont see why you have to stay away from car drivers? lots of 10" drivers have great specks these days.

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=295-462

60 quid each, 120 notes gets you 1200 wrms of 10 inch bass masness [/quote]

That's not a bad looking driver, but the 84dB sensitivity puts me off a little. Notice it's a 4 ohm driver rated at 2.83v. Subtract 3dB to compare with 1W on an 8 ohm driver. You will need a large part of that 600 Watt power rating to get a big sound out of it.

Good point about the 10" Pro drivers Adrian. Most Pros consider a 10" to be a mid driver, not a subwoofer.
I'm not against car subs at all. In fact, I have 4 WOs in service on friends' PA systems using car subs and they sound really good for their size.

JRock, are you gonna give'em a try in a db or a wo ?
8bit-ash, if you are considering the daytons, inform yourself about the taxes because they can be pretty heavy.
EDIT :
gex, jet's modded wos are similar to ported boxes.

you have to look only at the SEALED chambers. the front chamber on the wo is the "compression" chamber.
just sim a 4th order, tuned @ 40hz, and write down the size of the sealed chamber. then compare it to the sealed chamber on the wo

bulid the thing, put 2 good 10s in it, throw decent power in and forget about it

all i can say is that steve said not to move the baffle back because the box would get boomy. this would mean a decrease in the sealed volume and an increase in the compression chamber.

cut the mitres this evening.  nice and easy as they were nearly all the same.

Its still 15" tall at the mo so need to decide tonight if i'm gonna cut it down for 10's or risk it and try 12's ???