Originally Posted by MBentz
I've been meaning to chime in sooner, but work has been way crazy hectic lately. I've actually been working on almost the exact same application for a few months now so I think it would be interesting to compare notes. I was actually targeting 20Hz to 150Hz, but scaling it down would be no problem.
However, what is driving the 380L requirement? And what are the SPL targets? The idea I've been working on is meant to be a modular/scalable approach, and the target transportation size should be smaller than 380L and weigh less than 100lbs. However, when unpacked, I think it's going to be larger. I'll have to crank the numbers later.
And then how many cabs were you going to build? I think you mentioned only one, but that wouldn't be very good for a FOH system....is this for your drum monitors on stage?
Btw, have you read Keele's paper on the comparisons between horns and vented cabs of the same volume?http://www.xlrtechs.com/dbkeele.com/...%20vs%20DR.pdf
I'm not sure I agree with Keele's conclusions, but I thought I'd throw the article out there as a discussion point.
I was wondering where you've been at...
This cab here is for fun basically.
It's a fact finding mission as I mentioned before. There are some concerns about the cone holding up at 3/1 compression, throat distortion getting out of control or other weird overload issues in the constricted area near the driver and I also wonder how the driver will behave thermally. Basically myth busting that long throw big woofers, with low efficiency like these don't work well in horns. If it happens to work out well, then a whole bunch of possibilities open up. Either way hopefully we can learn something.
I'm almost done with the ported B&C cabs which cover the same range but are smaller at about 15cu ft external. Part of me wants to just do a TH with one of those drivers for an apples to apples, but we already know that the B&C will work well if done right. In the end I'll probably end up with 4 of some design or another for a foundation of a personal rig.
The reason for 380-400L is because I'm trying to come in at about 18cu ft external for the cab. Everything is based off of external cab size and what can be fit inside. 18cu ft is about the range of the average double 18" pro bin. I'm trying to make a horn that can outperform a good double 18 in the same cabinet size. It is not that easy at least according to the simulations. I can do perhaps a little better (efficiency/output 30-100hz), but I have not been able to beat the double vented cab that I would build
with both having the same low corner. It wins slightly on efficiency, cone excursion and having twice the drivers would win on power handling and compression.
. I can cram double 21sw152's or 21NLW9600's into a cab that is about 19cu ft external, with slightly undersized vents. It would not be easy but I have a rough cab design worked up.