That would be a key signature of one flat.īut your descriptions hints at the possibility of D minor. There is also the possibility of modes being involved but in the simple world of just major and minor keys then you are probably looking at D minor. I say 'common' since I don't want to assert that no one uses weird key signatures with oddities such as a F natural and a C sharp. So, for the question in the title: no (common) key signature contains those notes.įor the question at the end of the body of the question: if the key signature is one flat but many accidentals are used to give B natural and C sharp then it is probably D minor rather than F major.

This will not usually be done by changing the key signature but with accidentals. The usage in a melody will be more complicated and up to the composer but it will be common that the 6th and 7th will be raised sometimes and not others. When descending, these changes don't happen and the B remains flat and the C remains natural. So, in the key of D minor, the B flat would become a B natural and the C natural would become a C sharp. A melodic minor scale will raise the 6th and 7th notes by a semitone when ascending. The key signature of D minor is the same as that of F major and has one flat which is B. However, that combination of notes will be common in a piece in D minor. All other keys signatures with sharps will also contain F sharp. The only key signature with a single sharp is G major / E minor with an F sharp. No common, standard key signature contains that combination of notes.

Key of c fife sharp knotes