What exact is this revelation and how does it emerge from Marsh experience of listening to Rock and roll?

The revelation emerges from Marsh's experience of listening to rock and roll as a transformative moment that deepens his understanding of the genre's cultural significance. Through immersion in the music, he recognizes how rock and roll serves as a powerful medium of expression that encapsulates the emotions and struggles of a generation. This realization highlights the way music can transcend mere entertainment, becoming a vital part of individual and collective identity. Ultimately, Marsh's experience illustrates the profound impact that rock and roll has on listeners, shaping their perspectives and connections to the world around them.