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Why was clair de lune written in D flat?

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The piece "Clair de Lune" ("Moonlight") by French composer Claude Debussy is one of the most famous pieces in the repertoire. Generally, it is performed in the key of D-flat major, which is a very dark, mysterious sounding key. The use of this key fits the mood of the piece perfectly, as Debussy wanted to evoke the mood of the night sky and a distant, shimmering moonlight. The piece utilizes several chromatic notes that would not be present in the key of C major, which is the home of the white notes on the piano. This gives the piece an added sense of mystery and beauty, as the subtle shifts and nuances in the melody create a unique atmosphere.


Do you music theorists agree?

Billy

“Amazing! I’ll be working with Jaco Pastorius, Charlie Parker, Art Tatum, and Buddy Rich, and you’re telling me it’s not that great of a gig?
“Well…” Saint Peter, hesitated, “God’s got this girlfriend who thinks she can sing…”