The Roar, The Lead, and The Joy

Three components that I hear, when I hear something that speaks to me:

1. The Roar is the sound of an artist fully committed to the emotional truth of his work.  It can correctly be described as an absence of doubt, but it is more precise to say that it's the positive and willful connection to primal energies within the mind, in the service of whatever statement the artist is trying to make.  See: Joe Cocker, Billy Idol, Jello Biafra, Barbara Streisand, James Jamerson, James Brown.
2. The Lead is an instrumental technique that distinguishes, sonically, the performance.  It occurs when a particular player has internalized the material to the extent that he pushes the composition forward temporally, by anticipating the next note.  The effect is subtle because the player must not play too fast- for example, Keith Richards is the rhythmic lead in the Rolling Stones; he leads, ever so slightly, Charlie Watts, and thus propels the rhythm forward.
3. The Joy is a function of the group dynamic, and of the conceptual content of the material.  It is similar to the Roar but exists before the performance, because it is the result of how the artists have chosen to approach the material.  Example is Yes covering Simon & Garfunkel, "America"- this recording is emblematic of the bands' basic approach, which includes a commitment to convey emotional positivity.