"Hi, my name is Marcus Milius. I play harmonica. I got a degree at the University of Southern California, a Bachelor's of Music, in Jazz Studies - Chromatic Harmonica. I play and teach harmonica here in New York City, and I'm happy to show you what I do.
The Diatonic harmonica is probably the sound that you are most familiar with when you think of harmonica. A lot of chords and a lot of bending, which is different than the chromatic harmonica. The diatonic harmonica is set up in one key and so you'll need twelve of them to play in every key of music. So when you have one, you've got just one-twelfth of the total instrument . The basic technique of diatonic harmonica is pretty simple because it is setup in one key. There are no wrong notes. By simply blowing or drawing, you are going to get notes that are within the key, so there are no wrong notes. You'll be playing chords by just opening and blowing through the harmonica, or drawing you get different notes. Single notes are obtained by tongue blocking or pucker method. The difference with diatonic harmonica is it uses a technique called bending to fill in the notes that are not in the key. For instance I have a 2 draw which is a G here, but I don't have an F below that. If I blow, I go to an E. So that's 2 Draw. And I want the note that's in between there, I can bend down to it. There's the bend. So I can fill in the major scale. There's the bend. And there are two bends in the major scale. Otherwise, I would not be able to play those two notes the F and the A in the scale. So, bending can help fill in the other notes, and also adds a character to the diatonic harmonica, that is very unique. You can slide into notes. There is also a technique called overblowing, a similar concept. With the overblows and the bends, you are able to fill in all the chromatic notes that are missing on the diatonic harmonica. This is an overblow it goes up rather than going down. Bends go down in pitch, Overblows jump up. Here is a bend, it goes down and here's an overblow. And that fills in all the notes that are not in the key the sharps and the flats. So you can actually using bends and overflows get a chromatic scale on the harmonica. "