I have a Rumble 100, I'm needing to be a little louder. I was looking at upgrading to the 200 or 500, but it got me curious about something. If I were to buy a second rumble 100 and play through both at the same time, would that have a bigger impact than selling the 100 and playing through only the 200? Which would be louder: twice the amps/speakers or twice the wattage? I guess the real question is, how does volume work as far as it's additive properties? Like, if you have two sound that are both 50dB, do they together make a sound louder than 50dB? Or does the thing at the highest dB level just set the overall max for the mix of sounds? If something is 50dB and something else 52dB is the resulting combination 52, greater than 52? I'd like to know both how volume works in general as well as if 2 amps are louder than one? Thanks