To get a feel for the performance capabilities of the SUB 2 in comparison to the SUB 25, we can use the published specifications to calculate the displacement of each subwoofer, which is fundamentally related to the SPL that each system can reproduce.
The effective surface area of the drivers less the foam surround is missing from the Paradigm literature, but the original SUB 2 press release stated “six 10-inch drivers move as much air as a pair of 15-inch or a single 21-inch woofer”. I will assume this means the SUB 2 has twice the effective area as the SUB 25.
Paradigm also states the SUB 2 drivers have 50mm (almost 2 inches) of peak-to-peak excursion, and the SUB 25 has 76mm (3 inches). The peak linear displacement used to calculate the system displacement is one half of these values.
Using the above values, I calculate a displacement of the SUB 2 to be 5700 cubic centimeters and the SUB 25 to be 4300 cubic centimeters given a 15 inch effective surface area. I find it interesting to compare these values to the chart taken from the Richard H Small paper “Closed Box Loudspeaker Systems Part 1: Analysis” :
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The effective surface area of the drivers less the foam surround is missing from the Paradigm literature, but the original SUB 2 press release stated “six 10-inch drivers move as much air as a pair of 15-inch or a single 21-inch woofer”. I will assume this means the SUB 2 has twice the effective area as the SUB 25.
Paradigm also states the SUB 2 drivers have 50mm (almost 2 inches) of peak-to-peak excursion, and the SUB 25 has 76mm (3 inches). The peak linear displacement used to calculate the system displacement is one half of these values.
Using the above values, I calculate a displacement of the SUB 2 to be 5700 cubic centimeters and the SUB 25 to be 4300 cubic centimeters given a 15 inch effective surface area. I find it interesting to compare these values to the chart taken from the Richard H Small paper “Closed Box Loudspeaker Systems Part 1: Analysis” :
