Depending on your goal there are a few factors to consider. Powered subwoofers have become much more sophisticated with the inclusion of EQ and or room correction.
My Supernova benefitted from the Velodyne setup program. Still the Supernova is limited to crossover, and volume. IMO having multiple EQ presets with my Velodyne DD makes adjustments to film and music audio a snap. With the Supernova I have to adjust a very sensitive volume attenuator.
My experience with the fathom is simply showroom. In that context they seemed to be a fine sub sonically. You'll notice some of the review testing was done using the Velodyne program. I'm not trying to make a point for Velodyne but their day to day usability suits my requirements for adjusting the sub to fit the material I'm listening to.
Two subs can load a room better than one but it's not necessarily a requirement.
My Supernova benefitted from the Velodyne setup program. Still the Supernova is limited to crossover, and volume. IMO having multiple EQ presets with my Velodyne DD makes adjustments to film and music audio a snap. With the Supernova I have to adjust a very sensitive volume attenuator.
My experience with the fathom is simply showroom. In that context they seemed to be a fine sub sonically. You'll notice some of the review testing was done using the Velodyne program. I'm not trying to make a point for Velodyne but their day to day usability suits my requirements for adjusting the sub to fit the material I'm listening to.
Two subs can load a room better than one but it's not necessarily a requirement.