I was going to sell my KHL 10" and get an Axiom sub, but read an article that said the better way to get more bass is to add a second sub. So, for just another $99. I added another KHL 10", and the results are terrific. Now I'm getting bass I can really "feel"! Plus, you can set the 2 subs to different crossover points, which extends the overall experience even more!