The amp is the X150......the speakers are a 4"BLH. The speakers are in corners..the room is 16 X18. The SPL was at the couch. The distance from the right and left speaker to the SPL meter was 15 feet. My buddys' name is Larry....he is a musician and plays around town a couple times a week. Believe this or not. I don't care. This is in his own words.............

I'm Larry, and I just sat here 15 feet away from the system listening to Metallica playing Enter Sandman @ 106 db peaks. The average volumn during the quiet portion of the song (the speaking part) was 100 db. I could detect absolutely no audible distortion at any point. In other words, the system kicked ass! Yes..I am a musician; and I know what loud music is supposed to sound like. The bass response was just fine, and there was certainly no need for a sub woofer at that volumn. I have previously listened to the system with a sub woofer, and it probably sounded a little better at low volumn; but I never really thought it needed one.

And that's the way it is....and all he would type! I simply asked Larry to type what he heard.

Now, other than a BLH....exactly what single driver design with a single 4" driver, can make those SPL's? A TL, a BR , a sealed......well not that I have been able to see actually demonstrated. Keep in mind we are talking a 4" single driver, not an 8, not a multi driver, but a single 4" driver. It seems that a BLH just might have an efficiency edge over other designs, unless of course one of them can achieve the same outputs using a COMPARABLE size driver. The BLH is a much more efficient type of design, I have found. I will give examples of real speakers in my next post....which may not be until tomorrow. In the mean time and I have said it over and over....in the world of single driver speakers....efficiency and small cones are your friends. Excursion and low efficiency is your enemy......My opinions OK.
Ed

BTW...I did not edit or spell check Larry's writings!