Harmonica is mostly rectangular in shape with many free reeds present at the top. Free reed instruments were created in the early 18th century. Harmonica began being created in the early 19th century in Europe. Harmonica is made up of the main body comb, reed plates which is nothing but the group of reeds and the cover plates. Since the original sound coming from harmonica is low, any sound amplifier will also be present inside the Harmonica. There are many types of Harmonica: 1) Diatonic Harmonica 2) Chromatic Harmonica 3) Tremolo Harmonica 4) Orchestral Harmonica are some of the types.
Harmonica works based on the factor pressure. The pressure created inside the Harmonica by blowing the air through reeds, makes the reed to vibrate which in turn creates sound. The sound amplifier present in it amplifies the sound and gives us amplified tune. All reeds are different in shape and size. The tune produced as output from each reed so varies. The harmonicas are often called as mouth Organs, harp etc. Harmonica is a simple device and learning and playing the desired tunes is very easy compared to other musical instruments. Harmonica is very often using at country music.