There are alot more factors that go into the sound of a subwoofer than its size. WIth a speaker there is no nature. Ive heard 10" that sound 10x sloppier than an 18" sub that Ive played with. ANd FYI, sensitivity of a woofer has about 1000000x more to do with response than the diameter of the cone.
If ignorance is bliss, why aren’t more people happy?.