What exactly is critical listening? Who does it?

i know for myself personally i find the deepest most meaningful feedback about where my system is from non-critical listening.....where i am just listening without any specific agenda. it’s when the full wonder of the music seems to happen

As far as I am concerned, @mikelavigne nailed it.

I don’t trust anything I think I hear when I focus on gear and system. I take mental notes, just in case, but sound quality insights aren’t real until they bubble to the surface at the detour of a piece of music I particularly enjoy, when my mind is lost a world away from equipment. If they do, when they do, then I know I can trust them.

@immatthewj 

Thank you for the remembrance. In my early years I was a huge rap fan. Critical listening was very important in my early formation years.

Since my early years analyzing the merits of rap, I have moved on.  

I've learned that satisfaction in the pleasures of life is elusive and rarely achieved if not for just a brief period of time.  We endure frustration and disappointment very often in our lives.  No matter how good it gets, sadness is ever present. 

Have a nice day.

Since my early years analyzing the merits of rap, I have moved on.  

I bet that took at least five minutes.......

critical listening is something I must do in the process of audio restoration of old damaged recordings. I must be sensitive to various audio anomalies common in older audio recordings. above all, my restoration results must seem nominally "musical" to the average ear. that means, in effect, "no shriek or boom" unless it is in the recording itself.

It’s clear to me the engineers involved when recording and mixing the end musical product as well as those people involved in the transmission of sound through the various Data pipes to our homes for Home Theater streaming purposes at times may not be fully in touch with what critical listening means

It’s very clear that Home theater streaming sound quality is substantially less than it should be and should significantly be improved but for some reason critical listening is not resulted in any effort to achieve this.  .