After many many years, I started back at piano lessons, including theory, last year. I really didn't have time to practice, and this year I don't even have time for lessons, BUT it really got me listening to music with a new kind of attention. Luckily, the radio is like a never-ending course in the never-ending stream of Western Classical Music. My favorite is CBC Radio 2.
Aside from keyboard convenience, and possibly referrals to prior works, I have not yet really understood why one key might be chosen by a composer over another. OK, Bach worked his way systematically through all the keys, and Beethoven kind of worked through most of them, but that is not quite a reason why any piece is set in any particular key.
I can't remember what stray fragment generated the idea that D minor is the saddest key. I LOVE sad music. D minor being sad has to do with the ancient Dorian mode, apparently. I don't have a clear understanding of that. I have been thinking about it a little bit for over a year now, and looking it up here and there when I get a chance.
There are some pretty impressive D minor pieces. I just heard Fauré's Quartet in D minor on the radio. Brahms, a famously sad and tragic guy, wrote his stunning Piano Concerto #1 in D minor. I understand that Haydn's String Quartet, Op 76 No 2 is in D minor, and is called the Witch's Minuet. Promising. Bach has some sensational work in D minor. Love Bach in all keys. I was curious about Swan Lake - famously tragic also, seems to be B minor. As for Beethoven's well-known sad Piano Sonatas, Op 13 - Pathétique is in C minor and Op 27 Moonlight is in C# minor. He did write Op 31 No 2 in D minor (must listen), which was apparently inspired by Shakespeare's "The Tempest". I am wondering if Prokofiev or Saint-Saëns used it, or Rachmaninoff. Is it pop-sad or really sad? Where does Wagner use it, if he uses it?
The marigold wonders nervously:
Is D minor the saddest key?
What could make D minor sadder than the other minor keys?
What is the saddest music?
And even more nervously:
What about the keys of sad pop music?
I guess I should look up a few songs that I think of as sad, and see if I can figure it out. John Lennon should be the optimal starting point.