Don´t be sad my friend. That´s the power of the music, it makes you feel happy or melancholic , depending of the moment. But think that is momentary. As psychologist you know this better than me.
P.S. your new photo remembers me Freud :-)
Peter, that´s the voice of a dramatic tenor, something between the baritone and the lyric tenor. In Kaufmann´s case, his voice is a bit more dense and thick, than others, but he achieves the high notes of a lyric tenor easily. By the way, Placido Domingo did the same. Give a look in the other voices in my post IV (Jon Vickers, Siegfried Jerusalem) and you'll see what I´m saying.