Mike and mojomike's posts covered the basics. The long story short is that the SubMersive is significantly more efficient to do its thing with 1000W vs. the JL with 2500W, and really only gives up ground in the aesthetic and size for a significantly lower price. I will be curious to see some more of Ilkka's testing which will shed some more light on exactly what the F113 is doing, particularly in its frequency response. The SubMersive has some real strengths in the upper bass dynamics and headroom, which is where much of that slam and impact lives. The SubMersive is also very smooth through the upper frequency range. Reports I've heard have indicated that the JL subs do high pass in the mid teens, so you won't get the extended VLF coupling that everyone has observed with the SubMersive. I do feel all of this adds up to an audible difference, and IMO, an advantage.
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