Question: what is the difference between a c and g harmonica?
Answer: When buying a harmonica or harp as they are commonly called, a "C" is for playing popular songs, whereas a "G" (in the key of G) is commonly used in country songs. ... Diatonic 10-hole harmonicas come in all major keys A,D,G,C,F,B,Bb, etc. They're also available in Minor Keys.