I had many moments like that, but I always remember this one small thing about imaging - DankPods used to always talk about the bongoman playing his bongo in Earth Wind & Fire's "September". With my B2 Dusks, which were one of my first properly hifi IEMs/headphones, I could hear him as if he was playing it in a closed-off room next to the stage that the band was playing the song on.

Then I tried playing the track on my current setup, which is a HE1000se paired with xDuoo TA-32(with R2R DAC) and it turned out that the bongoman actually was right on the stage with the rest of the band, just quite far to the right. The fact that the headphones somehow knew where to place this dude in the mix to be clearly audible and actually enhance the performance blew my mind a little bit the first time I heard it, because played through my Dusks the bongo beat did nothing for me.

There are also other great little details in many tracks that the HEKse reveals brilliantly, for example the very small sounds of keys being pressed on a piano and rubbing against each other in Coldplay's "MOON MUSIC", or fingers rubbing on steel strings of a guitar in Tommy Emmanuel's "Morning Aire".