Power input means nothing without sensitivity. JL Audio drivers are not normally very sensitive. The drivers used in the Gotham 213 are the
13W7Ae drivers. 86dB for 1w/1m is OK but it isn't above average. It uses a heavy moving assembly, so it takes a lot of power to get the cone to move. The upside is that it can handle a lot of power. The downside is that it needs double the power to equal the same output of anything that has an 89dB sensitivity. What is more is that in a G213 the drivers are placed in a tight container which reduces the sensitivity of the system as a whole. In comparison to the Hsu VTF15h sub, that is a more sensitive driver that is given a whole lot of breathing room in a large ported enclosure. It doesn't need a whole lot of power to reach big SPLs.
The G213 is a very nice sub, but it necessarily constricts itself to pack a lot of power in a small footprint. The reason why the moving assembly of the driver is heavy is for a lower resonant frequency so it can play the lowest octave more easily. It is marketed to people who have a lot more money than floorspace, so they need to squeeze the maximum performance out of a small footprint and also look really nice while doing it. That is an expensive endeavor, but the G213 does it pretty well. However, if you relaxed the size constraints as well as aesthetic constraints and luxury build quality, you can get similar performance for a whole lot less money. Consider the Hsu to be a tuned Supra and the G213 to be a Ferrari. Even though the Ferrari is much more expensive, it isn't going to be pulling much higher track times, but it is undeniably a much nicer car regardless.
