When I soke of chanting at a High Mass, I was speaking of the choir singing Gregorian Chant, though I do remember being at a Lithuanian Franciscan monastery for a Benediction and the monks chanted all of that service. This would have been in the late 50s.
I was referring to the same, when I mentioned I'd never heard it sung.
The only recording of chant I have is a recording by the Tallis Scholars.
I have somewhat low blood pressure, and I can easily tell when it drops, and within a minute or so of hearing this CD my heartrate slows, and I can feel my bp drop. That's the kind of calming influence Chant has on me.