The 10 hole harmonica in Europe and the United States are called it "10 - Holes， Harp"， sometimes referred to as "Diatonic Harp" (Diatonic harmonica)， or call it "folk harmonica" or "Blues Harp" (the Blues harmonica)， in fact is about the same kind of harmonica.The harmonica is very popular in Europe and the us is the biggest ethnic group in the harmonica lovers， estimates that 99% of the world's love for the 10 hole harmonica people choose it， single spring， every hole two notes， a total of 20， about three octaves.Usually have A common characteristic， A 10 hole harmonica is the bass is not F (Fa) and A (La)， note no B (Si)， the consideration and specially designed for harmony.If still can apply bending (bending) technique to play out the lack of scale.On such a scale design actually dates back to 1825 a Bohemian instrument craftsman Richter， appear this kind of scale improvement and innovation system.When you blow out 1， 3， 5， a set of sound C， chords， and breathe in 2， 4， 6， or 5， 7， 2， 4， a set of sound constitute the G7 chords， to play folk music is very suitable for at that time， especially rich in blues colour.