3D40.60 • Music Box
Location: Floor Demo
Photo shows the demonstration used at the University of Texas at Austin.
Photo shows the demonstration used at the University of Texas at Austin.
Concepts Conveyed:
- Shows how a music box works on a fundamental level in a larger view.
- As the prongs hit the comb, it will cause them to vibrate at a specific frequency, acting as a simple harmonic oscillator, which will produce a sound.
- The longer the prongs (the further the prongs from the comb’s edge), the slower the comb will vibrate, resulting in a lower pitch. Shorter prongs will vibrate the comb faster, producing a higher sound.
- The thickness of the comb of a normal music box also varies. Longer teeth (lower notes) are typically weighted at the end, which lowers their resonant frequency. However, since this is just a model, the thickness of the comb is all even.
Instructions / Notes:
- DISCLAIMER: The music box is just a model, so the notes played will not be accurate. This is due to the material of the comb not being the same as a typical comb.
- Turn the drum of the music box by using the handle so that the prongs hit the bottom of the comb (counter-clockwise). Start where the drum is labeled “Start Here”.
- The first two notes should be the same (the beginning of Happy Birthday), although you may have to listen very carefully to hear it.
- Each prong is labelled with its corresponding syllable in the song.
Demo Staff:
- Make sure the professor knows this is just a model.
- Ensure all the prongs can hit the comb when testing. If not, adjust the distance of the barrel to the comb.
- Be careful with the prongs when transporting! They can be sharp.
- Provide the little music box too!! It actually makes music.
Last updated on April 14, 2025