There have been occasions where a song has been recorded in C, but then frequency shifted to C#/Db to make it more awkward for other people to copy/play. There are probably other reason, too.

Historically, instrument tunings also varied, so different keys could have different characters. Modern equal temperament tuning mostly circumvents that.


Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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