The dual 12's have 1.3 times more surface area than a single 15" though, so wouldn't four 12's be better than two 15's? I understand and agree with everyone's recommendations, but I need to compromise on footprint so I'm trying to find a happy medium. Why was two PC2000 recommended (two ported 12's) but four sealed 12's is not?
I've heard, mind, that the L series Rythmik sells is also underpowered compared to many other options. This is why you might see us recommend Hsu as the value leader... Bang-for-the-buck...
Nothing else matches their performance level at their cost. When you step up to the next level higher, you are looking at Fit and Finish improvements over what Hsu might offer, I think.
As you move up the Rythmik ladder, you find Aluminum cones and higher powered amps. These undoubtedly perform better than the Paper options.
Another aspect to consider is that not all drivers are equal. The cone material is one thing, and then there is the Motor. A well designed motor can make a significant difference in the cost...
AND the performance of the driver. Power handling and mechanical travel distance are just two aspects that are more easily understood. The compliance of the driver gets a little more difficult, but is equally important.
Stacking two of those 12" paper cones as Rythmik has increases output and it will likely perform slightly better in your room than even a single better 12" driver from its output potential alone. But...
I would not favor that sub, however, to hold up to a better designed product in terms of all other aspects. (I do consider the PC2000 to be a better designed product, just based my research.)
Back to your question, surface area will move air, but to what effect if the cones and motor structure start to fail at lower SPL and Frequency. This is a hypothetical: I have not seen a review for the Rythmik paper cones that I can recall. I cannot predict its overall performance. I have, however, been cautioned about going in that direction when I had hoped to save some coin.
Beyond that, as intriguing as the Servo technology is... why do more companies not pursue it? Cost? Production complications? Implementation? Efficacy?
I found Sub shopping to be about balancing tradeoffs. I required extension for Pipe Organ... 16Hz. That requires something different than somebody just wanting to enjoy HT on the weekend vs a power user vs an audio head...
I believe that finding the best sub at producing high quality SOUND across the spectrum, which will meet the need of SPL and extension is the first step. If the aesthetics are a concern then they come third after making certain the Amp will work in your system (which includes all connectivity and UI aspects of the Amp)!
That's me.
A good driver will perform well for both HT and Music. A well designed and built Sub will do the same.