When Did Your System Disappear?

As we upgrade our audio systems, things (hopefully) keep sounding better and better. I have found that after a certain point, the system completely disappears. It’s no longer a pair of speakers, amps, preamps, sources, etc. Music is created out of thin air floating between and behind the speakers with little to no colorations in the sound. The regular audio verbiage can be thrown out the window because all you hear is the recording. If something is bright or harsh or bass heavy, it’s the recording not your system.
I noticed this when I modified my source and preamp to accept better power supplies. Using a combination of linear power supplies and large SLA batteries took my system to a new level where the equipment just disappears. Of course, this wasn’t the only thing that helped. Up to that point, every component has been experimented on to achieve a high degree of synergy. Interconnects, power cables, speaker cables, etc. all play a role too. Everything matters. 

My question to you all is when did this happen in your system? Did it develop slowly over time or was there a definite change that occurred with a certain upgrade?
Surprised this hasn’t been mentioned yet:

1. Speaker positioning

And since these areas haven’t been covered...

2. Some (let’s say) ’brains’ are more "open" / "amenable" to the suspension of disbelief...

3. Recording dependent. Certain recordings (there are many) shouldn’t (do not) result in "disappearance" (mic positioning, etc.)...
Not easy to hide my Vandies in my room, but achieved a great disappearing act with room treatments a couple months ago.. Changed everything....then got my new preamp today, and its getting harder and harder to find them....depending on the quality of the recording of course.
Last week, actually. I was sitting in my chair flipping through an audio magazine while the music was playing. Then the vocal came on and I literally jumped and looked up because it was as if the singer was standing 5 feet from me. It was quite surreal.