An diatonic instrument is designed to play only one musical key. You need one another for each different musical key you want to play in. An instrument that can play In one key is a chromatic instrument. The diatonic harmonica was the first mass-produced in 1857 by Matthias Hohner. By 1858 he began shipping them to America. They were meant to play German and European folk music. They adapted well to the American folk and country music. The harmonica I had learned to play on the Hohner Marine Band. The was the basic ten-hole diatonic harmonica, which is sold in that form from 1920.
The basic ten-hole diatonic harmonica is designed to play songs simple major. The harmony this song is based on the tonic and dominant seventh chord of a major large scale. Since these are built on the first and fifth note of the large scale, they are often identified with Roman numerals in the I and V7 chords. Blues harmony is different. It has two main agreements are based on the first and fourth note of the large scale. In Roman numerals would a I and IV agree. These two chords are dominant sevenths. Let use the C major scale to help explain.
The natural musical tones a, b, c, d, e, f, and g. If you start on the note c, you c, d, e, f, g, a, b, c. This gives you the do, re, me, FA, so, la, ti, do a large scale. Start on a Another remark and you have to make a character widely, depending on which note you start on. In the key of C major, the I and V7 chords C and G7. Suppose we want to play blues in the key of G major. The extensive notes g, a, b, c, d, e, f sharp, g The I and IV chords would be C and G or G7 or C7 for blues. The fifth note of the C-scale and four G of the C. So you can see that if we are the chords for a simple song in the key of C major and play them back, using the V-belt for the I and I to IV, we have Blues in G major.
Now we have the notes in the chords to learn. For many chords, we take note we start and then every other note. The formula is 1, 3, 5 for a major chord. So for a C major chord starting on C, the notes C, E, G. When you blow the ten hole diatonic harmonica in the key of C major, the notes C, E, G, C, E, G, C, E, G, c. In other words, if you blow into the harmonica, you play a C major chord. Starts on ag for a G7 chord we have 1, 3, 5, 7. So the notes in G7 agree g, b, d, f.. If your breath or draw on the ten hole diatonic harmonica in the key of C major, the notes d, g, b, d, f, a, b, d, f, a. A note is not one of the fundamental notes of the chord G7 but doing well. So if you based on the harmonica, you are basically playing a G-7 agreement.
When the diatonic harmonica to play the way it was designed to be played, you learn to play the melody notes as you explore and cover the other holes with your tongue. With your tongue extracted from a chord melody and accompaniment of your cupped hands of other effects, you really sound like a small band. How has this simple folk instrument became a blues harp. In the 1920 harmonica players began to discover how a different sound. They found that if you played it backwards, using the draw chord as your primary agreement and the blow chord chord as your secondary, you have a blues sound. It's called cross hammering. Your chords C and G7 on the draw on the hit, you play blues in G on your C harmonica. This is called cross hammering. Add the technique of drawing over the explanation and amplification curve and you have the blues harp. When you hear, performed by a talented player, it's amazing the sounds them out of such a simple instrument.