I have read that for every 3 dB difference in speaker sensitivity the required power to drive the speakers either halves or doubles. Is that to say to power a LSi9 which has a rating of 88 sensitivity would require 100 watts to equal the sound level of a CSi40 which has a rating of 91 at 50 watts. I think I am confusing myself because this just doesn't sound right. I realize there is an impedance difference between these two speakers. Does that factor in. I used these two speakers just for comparison purposes.