No free lunch

The sensitivity rating and impedance of your speakers are important specs.

In other words, they go hand-in-hand. 

SPL is what you should focus on. A safe level of volume....comfortable for several hours of listening without ear fatigue or headaches.

Interesting to be conscious reading that article about the great amount of trade-off related to any engineering master craft....

Did we all watch the same video? Because the one I saw there was nothing about any free lunch, nothing about impedance, and zippo about tradeoffs.

So either we all watched different videos, or people "get" stuff that never was there. I know which one my money's on. But hey, feel free to prove me wrong. It's a video. Simply point out the time stamps where they talk about 
1. free lunch
2. impedance
3. tradeoffs

Thanks!

Miller: the "no free lunch" side of things is introduced in the comments section by Mr. Chris Brunhaver of PS Audio, to counter the views of Sean Casey of Zu on his take on (the advantage of) higher sensitivity speakers. Not meant as a comment on high vs. low sensitivity from my side here, but just to point out the "missing link"..