Is E Flat a high note?

No. High notes are always low notes. But E Flat is definitely a high note. In any context other than a D string.

4. The F major scale is a D major scale

I can hear a small rattle of disbelief in your voice, a voice that never really understood this thing before. “But what do I play on a D string?” I ask. You’re a drummer. You’re a musician. You play in some band. What sort of question would this be from a drummer? “What do you play on a D string ?”

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You might say, “E Flat – D”. Yes. A D-major scale. But that’s not what E Flat means at all. What it means (or, rather, the F major scale) is that it’s D – major – just as E Flat is called.

Just in case you haven’t got this totally figured out, here’s another way you’ve probably lost it: E Flat is sometimes also called a dominant seventh. The seventh chord of any major scale is known as “the dominant seventh.” The whole point of playing seventh chords in this context is to create tension and resolve it with the next chord.

5. E Flat isn’t D-sharp

Now you might be thinking, oh, I see, then I can make E Flat sound like an F# or F major seventh. No. The E Flat used to sound like an F#. That was D major’s “natural” sharp and E flat was the natural sharp and D-sharp.

You see, this is exactly what you were worried about. You’d think this would tell me that if I played E flat and the string was D minor, that something was wrong. Something was wrong because I thought I was messing with the chords that D minor doesn’t use. But no, D major doesn’t use any seventh chords, it uses E major and it uses the fifth and seventh chords – as you can see in the scale diagram above.

6. E Flat is an interval between a C and a D

So it’s not actually an interval but an interval. And you’re thinking, that’s strange. But it’s true. You can think of E flat as being like an interval between the notes of D natural major and D major seven and C major seven. So E flat sounds like an interval between the C bass note, B, and the E bass note, C, which is Cmaj7