It is striking how some music simply feels uncomfortable when heard, even for the first time. Yesterday I heard some vocal music with organ accompaniment, a mass setting I do not recall ever hearing before. I felt uneasy as I listened, and finally figured out why: it was in an unusual key, one to which singers rarely have to tune. They literally were out of their comfort zone. And, in response, so was I.
Was the music intended to have that effect? I can only think that to be the case. When instrumental music is composed that way, the effect is often disguised by over-assertive dynamics, as if to cover up any likelihood that a listener might feel ill at ease. But what is wrong with feeling ill at ease?
The voice is so much more transparent in this respect, so much more immediately expressive!