Listener envelopment is a rigorous acoustic concept abbreviated by LV and the apparent source width abbreviated by ASW is also a rigorous acoustic concept ...
«The auditory system has mechanisms that separate the processing of late reverberation from the processing of direct sound and early reflections referred to as precedence effect. While the late reverberation contributes to the perception of listener envelopment and reverberance, the direct sound and the early reflections mostly affect source localization, intimacy and the apparent source width.[3] The balance of early and late arriving sound affects the perceived clarity, warmth and brilliance. » Wiki
Now in a small room or in vas hall acoustic there is means and acoustic design and tools to create IMMERSIVENESS which is the result of the right balance LV/ASW ...
I created it in my small room but not with only material passive treatment but i needed active mechanical one : aqn oriented grid of tuned Hemholtzs resonators around speakers and my listening position...
It was stereo on steroid as if i had many speakers... The recording trade 0ff of each musical album was plain to hear and astoundingly different between all albums..
All recording were interesting even the bad recording because the speakers/room revealed the recording engineer choices...
I lost my acoustic room selling my house, i was sad... I discovered the only headphone i can modify for my acoustic needs and now i came back here with an headphone system... An immersive one for an headphone without the BACCH filters or no dSP associated like the Smyth realizer... The K340 is among the few the best designed headphones ever...