Esmeralda and Phil explain the four different classes of musical instruments, when Cro does not understand the way a violin works.
George accidentally destroys the Man with the Yellow Hat's guitar, so he makes him a new one. He learns more about bluegrass music and its history of using handmade instruments.
What's the first musical instrument? Then Josie sings a song explaining it's the human voice.
Jeanine Head Miller explains the history behind the infamous violin which was once created by a legendary craftsman 300 years ago. She describes how the violin was able to be preserved in order to maintain the credentials of past history in musical instruments.
Huckle is struggling with playing the tuba, so Lowly reminds him that the amount of wind he pushes into the instrument will affect the sound.