Mozart continues to amaze. I’m not positive my interpretation is entirely right; I have some sympathy for those who want to stay in equal temperament, it’s much easier. But play measure 37 on your piano or organ: it will not sound good. That third in the bass, as sung, is much flatter and correctly flatter than the keyboard third.
The descending commas in the bass voice, bar 39, may be gratuitous, but they seemed right to me. In bar 35, last beat, I chose an out of tune vertical sonority in order to keep the perfect melodic intervals perfect.
I’m also working on Tallis, “If ye love me”: much less satisfying than Mozart. With Wolfgang, one knows that the music is great and the interpretation had better live up to it; with Thomas, one is much less sure about the quality, one has less fun interpreting, and the work begins to seem like dreary labor.