E Double Flat
c flat. the semitone above b flat is b, with is equal to c flat. So the diatonic semitone is c flat because it has to be a different note name.
It is called a "natural" sign, and it cancels out/naturalizes a sharp or a flat.
C-sharp to D, or C to D-flat would be a semitone.
C sharp/D flat
E Double Flat
A C flat
F flat.
B Double Flat
c flat. the semitone above b flat is b, with is equal to c flat. So the diatonic semitone is c flat because it has to be a different note name.
To lower a note that's already flat, there is such a thing as a double-flat.
It is called a "natural" sign, and it cancels out/naturalizes a sharp or a flat.
It is a note a half step above or below the original note (a sharp or flat).
Sharps are the note one semitone higher than a given natural note, for example, D-sharp is one semitone higherthan D.Flats are the note one semitone lower than a given natural note, so D-flat is one semitone lower than D.Natural signs get rid of a previous sharp or flat in the same bar, or raises or lowers a sharp or flat already included in the key signature - e.g. the F-sharp in G major.Sharps and flats can be modified further too - resulting in a double sharp or double flat - which means that any double sharp or double flat will be a whole tone higher or lower than a given natural note, for example, D double-sharp would be the same key as E and D double-flat would be the same as C. Again a natural sign would get rid of the double flat or sharp.Sometimes natural keys have to be named as either sharp or flat, e.g. in C-sharp minor the seventh degree is B, but we have to raise B to B-sharp to create a C-sharp harmonic minor scale, which uses a raised seventh. Now we could call the B-sharp 'C' but that would not be correct as we need to use all letter names in a diatonic scale, and technically the C is functioning as a raised B in the key or C-sharp minor.
C-sharp to D, or C to D-flat would be a semitone.
C sharp/D flat
flat