Originally Posted by Bass Thumper
Originally Posted by Gordon Scott
The notes are correct but I think that that there are a couple of spellings that should change.

Fdim would be F Ab Cb
A#dim would be A# C# E
Yeah, this is that enharmonic thing again.
I'm not sure if there is an absolute crisp solution that fully answers this.

This image is from pianochord.org but I'm not sure that even this is the "truth" . . .

I reckon rule 1 is to not get too hung up about it.

I think rule 2 is probably that sometimes things are debatable. MarioD said that the 'old way' he used was that a chord should have the same #/b symbols as the scale it's in, which would mean in his rules my + or #5 should be a b6, but to me the chord is still a triad, so it should contain the 5 of whatever persuasion.

For me the most important thing is about which notes in the chord I should raise or lower by a semitone (or two in the case of a fully diminished). Generally when one does that the notes do keep the same #/b symbol as the scale.

There's a fairly full explanation on the Hear & Play website, which follows the "same #/b" rule, but I think it doesn't mention ... oh, yes it does and get this ...
In one lesson it has:
Quote
The use of the sharp symbol should “raise” a red flag. It’s wrong to have a sharp symbol in the spelling of a flat-based major scale. Always remember that.
and in another it has
Quote
Some musicians don’t understand why I mixed sharps and flats.

Somewhere in their musical journey, they learned that either chords are sharp-based or flat-based (similar to how major keys either have all sharps or all flats). But this is wrong when it comes to sharping and flatting degrees.

In truth, I personally think the contradiction is probably unavoidable. It's a useful website, though mostly piano-oriented. It has 7 pages of explanation on this, which definitely indicates that it isn't always obvious: https://www.hearandplay.com/main/proper-spelling-of-chords

Remember my rule 1. laugh

Jazz relative beginner, starting at a much older age than was helpful.
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