I'm not clear on what everything means when reading the stats. These are the stats of a GK goldline cab, i'm using this just as a reference. 810GLX 4 ohms 800 watts RMS (What does RMS mean? what's the difference between this and something like program handling?) 99dB 55Hz to 5kHz (-3dB) (Why on the frequency response does it say -3dB?) 128dB max SPL Any info would be greatly appreciated, thanks!