Hi, adi. Let this be the moral of the story: never answer e-mail on Monday! I must again correct something I told you. My original statement that a doubling of volume is represented by a 10db increase was correct. I got a little confused after reading Danny's reply and went off the trail...
At any rate, Danny has sent a valuable link. If you read the section entitled "How much power do I need", you will find verification of the claims I made; specifically that a doubling of volume requires ten times the power. You may also want to visit Cinepro.com. I also hope that I did not give the impression that I don't think sensitivity is important; after re-reading my reply, I didn't really see anything that suggested that. I just don't see it as a litmus test. Luck...Jeff