Now let's have some fun!
Here's two variations on XOC1's box.
The first uses four of the Alpine tens.
The second uses SIXTEEN of the Alpine tens, but in isobaric pairs. (Box size is exactly the same.)
Here's the frequency response.
Yes, it's exactly the same.
Here's the impedance curve. Same here too.
Ah, here's the money shot!
The isobaric box has half the excursion. And since subs are generally limited by displacement, that means
the isobaric box will get louder than the conventional box, as long as you have enough power to get there.
The icing on the cake is you have four times as many voice coils. So thermal modulation and thermal compression will be dramatically reduced.
Of course, this box is completely unnecessary if you don't have a big amp to drive it
The Behringer Europower amp would be awesome on this. 4000 watts into this box works out to 250 watts per voice coil, which is well within the Alpine's limits. Heck, you could probably halve the box size, use half the woofers, and dump 500 watts into each one. Eight of the Alpine tens and one of the Behringer amps would cost about $1100. (Amazon and Wal Mart have the amp for $275, and the Alpine woofer is readily available for $100 at various retailers.)
[IMGDEAD]https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTV6HkxtS7F32jIyfxYcSR1-On-Bmg_GqwtsDe2bc5VYR4KcW3uwg[/IMGDEAD]
Now, obviously it's going to be a bit tricky to squeeze sixteen tens into this enclosure
A couple of options:
You could mount the drivers like the Tymphany LAT
or...
You could double the length of S4-S5
Obviously, the tens are 'home theater friendly' because you could take XOC1's box and halve the width. So instead of being 21" wide it would be 11.5" wide.