Originally Posted by CL400Peavey
Isobaric cabs are an antiquated design. Double the drivers to make up for a smaller box, and no volume gain from the second set of drivers.
The isobaric, exponential horn and reflex (vented) cabinets are all the same era, thus all antiquated.
Harry Olson detailed all three designs in his masterwork "Acoustical Engineering" first published in 1940.
The sole intent of the isobaric is reducing the required internal box volume by 50%.
It is not 2x louder, does not clean your room, nor do your homework.
Back in the antiquated era, cone mass was light, Vas was high, and a huge box was required to obtain bass response.
The iso design cut that huge box in half.
Today, a designer can take an Eminence BP102 down flat to 32 Hz in 4 cubic feet, or 32 Hz in 2 cubic feet, isobaric.
Driver cost and weight is 2x.
Cabinet complexity is at least 2x over a simple vented box.
It's all about the tradeoff.