I was wondering what was the biggest factor in a driver reaching its limits and "bottoming out". Is it mainly the sheer volume you are pushing through it or is it related more to the frequency of the signal feeding the sub vs the frequency the sub is tuned to, or neither or both? I assume it is probably both, so I guess my question is: Which factor is more important? For example, assuming everything else was equal (ie both subs calibrated to 75 with VE and output at reference levels), would the sub tuned to 16 hz be less likely to bottom out with the intro to Toy Story 2, TPM or the door knock on the Monsters trailer than a sub tuned to 25 hz? I know the 25hz tuned sub will pump out more spl's at 25hz and higher, but if your main goal was not to bottom on those really low, bass heavy scenes, are you better off going for a sub that is tuned lower? I am talking about passive subs with an external amplifier and no filters.