On this site and in my private lessons I always talk theory as if we’re playing a C harmonica. And I only ask you to memorise the notes of that one key. I’ve written about this already here: Why Do We Talk About C Harmonicas All The Time?
What I haven’t explained is how easy it actually is to do.
The C harmonica, as you might expect, plays all the notes of the C major scale. The C major scale is the easiest one to learn because it contains no sharp or flat notes. It goes like this:
C D E F G A B C
The note names follow alphabetically from C up to G, then loop back to A, and from there back up to C. These are the only notes naturally available on the C harp without bending, and they lay out like this.
Let’s look at the blow notes first. They follow a simple pattern. CEG, CEG, CEG, C. Pretty easy to remember that. As a mnemonic I think of the word keg (as in a beer keg).
The draw notes require just a bit more work. You need to commit the first two to memory. That’s D and G. The remaining notes follow the pattern BDFA, BDFA. A good mnemonic for that is Big Dave Fights Again.
So really all you need to remember for the blow holes is CEG three times with an extra C on the end.
All you need to remember for the draw holes is D, G, and Big Dave Fights Again twice.
Armed with that knowledge you can quickly and easily identify the notes available on any given hole. Since we have only ten holes you can even count it out on your fingers.
When I was learning this I roped my wife into testing me by calling out random holes and seeing how quickly I could identify it. You can do this yourself just by playing random holes and challenging yourself to name the note.
It’s pretty easy to get the hang of and I promise it will be useful down the road.