What is a "reference" system?

Is playing a brilliantly designed acoustic guitar a reference? It's in my lap and sounds different to me than to somebody who isn't playing it. Live music generally involves sound reinforcement using the ears of a sound mixer (like me...a certified old person), or reflections from a concert hall or the bald head of the guy in front of you. Do people listen to to live string quartets or jazz bands while lying on the floor between the musicians? You risk being stepped on. To me, a reference is what sounds good to me from whatever source...it's clear, coherent, and makes sense...if it doesn't make me "think" the sound is appropriately balanced and well played it isn't gonna make me feel good about it. Not reference-ish enough maybe. 

A reference system is a combination of components that provides a standard or baseline for comparison for determining the sound quality of a new component that is introduced into the system.  While some believe that the definition of a reference system includes subjectively the “best; most resolving; most neutral; most expensive” components, this does not necessarily fit with the idea of establishing a standard or baseline for the comparison of other components.  In addition, some believe that a reference system includes subjectively a system that reproduces sound most like acoustic, live performances.  While admittedly this is one of my goals for my system, personal preference and subjective interpretation does not enter into establishing a reference system.  If you survey the systems of some authors in the trade rags, some have the most resolving or most expensive reference systems but others do not.  So, a reference system is basically your system if you have established a perception , goal, standard or ideal of how you believe recorded and reproduced music should sound, and have developed excellent listening skills that permit you to  understand how your system sounds in comparison.  Then, you can introduce new components and compare the change to your reference.  

The ideal "reference" system would be that which is the most heard by the most recording engineers/people so that most everyone would have a common ground on which to base their opinions (i.e., a point of reference).

This is why I had previously alluded to the LS3/5As because most all British music is mixed, or at least sampled, over this set-up and most engineers would be familiar with the sound.

An American "reference" system would then include the likes of Altec 604s/JBL 4333s, at least for 60s/70s/80s music.

While not current state of the art, these were purchased from a recording studio and even at >45 years old this would qualify as a reference system.

https://youtu.be/iGa9259pz-I

 A reference system is defined by two factors:

 A--- The sound of  live acoustic instruments or voices experimented by each one of us in our life...

 B----Then the way the system room is acoustically designed for ONE listener to translate the recording in the best acoustic experience...

Great hall acoustics  dont use the principle and concepts  of acoustics for all listeners ears sitting in different position  in the same way a dedicated room did for the owner ears in one specific location...

Same acoustics science very different application...

There exist as many reference system as there is pair of ears...

A reference system is not about money and only gear pieces but about their acoustical embeddings...

the fact that some piece of gear are "reference" does not define a reference TOP system...

Well, I know you said you didn't want to open it up regarding YouTuber reviewers, but Hans Beekhuyzen has three "reference" systems. In his world, "reference" means three price points such that all components in each system are matched to each other in price.  In other words, he doesn't put a $10K DAC on a $1K integrated amp and $500 speakers. And yes, at each of these three price levels he switches review pieces in and out and lets you know what he hears and which system they are most likely a good fit (or not).