FWIW, I go with keeping the note letter the same, whatever that requires us to do with the accidental symbols (flat, sharp or natural) to achieve that. This conflicts a bit with Mario's system, but I'm not sure that holds firm with, for example, the outliers below. Of course in C, the key signature has no flats or sharps, so maybe we're off the hook in that case. The rule I was given was "you must not have two notes with the same letter within a chord". That would allow A instead of Bbb, but to me that feels wrong. Others may feel differently. I'm open to persuasion.

CMaj - C, E, G
CMaj7 - C, E, G, B
C7 - C, E, G, Bb
Cm7 - C, Eb, G, Bb
CmMaj7 - C, Eb, G, B
Cdim - C, Eb, Gb
Cm7b5 - C, Eb, Gb, Bb
and outliers
Cdim7 - C, Eb, Gb, Bbb
C+ - C, E, G#
C7#5 - C, E, G#, Bb
CMaj7#5 - C, E, G#, B

Last edited by Gordon Scott; 11/07/23 02:45 PM. Reason: yep ... typo
Jazz relative beginner, starting at a much older age than was helpful.
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