Originally Posted by Mfusick
Expanding a little:
My concern of integrating the side "smoothing" subs with main event subwoofer system is still in my mind. But I am not exactly sure if my concerns are well placed, or misplaced. Porting different systems at different tunes will change the phase and create small problems the same as if mixing a ported and a horn or a horn and a sealed, or a ported and a sealed (which is most problematic).
Odd question, anyone ever made a DIY slider system to close a port on a DIY system ? That seems easy to do too. I could switch from ported to sealed by blocking the port. It would be a big box for sealed, but would work. See.. I just get too crazy... haha
The problem with mixing dissimilar systems is that for the "smoothing" concept to work, they all need to be playing at approximately the same SPL. This means the total distortion of the system is limited by the weakest link.
And even if the distortions are acceptably low, the distortion signatures will be different. The last thing you want is more unwanted frequencies.
All that to say, I would highly recommend starting with REW's room mode calculator and actually identify where you need speakers located in the room. Once you've identified where the acoustic sources need to be, then you can decide which form-factors maximize your performance.
Seriously, start with the room modes. As awesome as some of these bass horns look, the mouth is probably firing into the wrong spot of the room.
ALso, have you read this thread yet?
You simply cannot get better modal response than this approach. Do it with whatever speakers you want, but the approach itself is so crazy elegant awesome and easy to implement.
Btw, you can splay a bass horn so that the sound exits in multiple locations....you could probably pull off something like this in the front and back of the room if you really want a horn.
As to your other question - yes, I made a variable port design about 10 years ago using a JBL 2226H. There were 5 ports and you could change the tune by plugging them one at a time - or plug all of them and go sealed. I would not recommend this approach anymore though and could go into the reasons if you really want to understand why. It has to do with optimizing the design of the port itself (there's lots of nonlinearities to consider and avoid).