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So for example, you spell the B major scale like so: B, C-sharp, D-sharp, E, F-sharp, G-sharp, A-sharp. All major scales are considered to be based on C major, and you are supposed to preserve the white keys’ names, modified by accidentals as needed.
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The usual answer is that you are only supposed to use each letter name once in any given scale. But what if you’re in A blues? How are you supposed to spell it then? And what difference does it make anyway? If you are in B major, the note is supposed to be called D-sharp, and if you are in B-flat major, the note is supposed to be called E-flat, that makes sense.
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I have since learned to use the correct name, but it still feels arbitrary sometimes, especially outside of diatonicism. I pretty much always called it E-flat, regardless of context. Guitars don’t have black and white keys, so when I was a feral self-taught musician, I just thought of that note as the eleventh fret on the E string, the sixth fret on the A string, the first fret on the D string, etc. You could also think of it as a lowered E, in which case it’s called E-flat.
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You could think of it as a raised D, in which case it’s called D-sharp. This confusion applies to all of the black keys, but in this post, I’ll be talking about the one between D and E. Why do the black keys on the piano each have two different names? If the posts on r/musictheory are any indication, this is a persistent point of confusion, especially when music theory teachers get all persnickety about using the correct name.
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