Hi! I'd like to sort this out and maybe some people here could help. I know that volume as to do with 2 factors : 1. the power to make a speaker move 2. the quantity of air that speaker can move So, well, I'm wondering. In theory (because I know, the design of a cab and of the speaker itself, among other things, have an impact), what would be louder : a bigger (say 15 inch) speaker with less (say 100 watt) power or a smaller (say 12 inch) speaker with an higher (say 150 watt) power rating? Purely in theory... I know what I' comparing here is not absolute.