Acoustics: Sound Creation & Propagation

This lesson is part of the Fundamentals of Sound & Music module.

Objectives

• Student will understand the basic nature of sound as vibration and how it propagates through a medium.
• Student will understand the concepts of frequency/amplitude and how they relate to pitch, loudness, and the media through which sounds travel.
• Student will be able to describe sound based on a visual representation on a spectrogram, time-frequency graph, or oscilloscope trace.

Resources

Readings

• Music Tech Musician:
  • Lesson 2: Physics of Sound
• Elsea, USCS Electronic Music Studios Technical Essays:
  • Sound.
• NDT Resource Center: "Sound"
• Physclips: "Pitch Loudness and Timbre."

Listening or Videos

• Physclips: Sound.
• Project Studio Handbook:
  • Waveform Diagrams.
  • Waveform Diagram Frequency and Amplitude.

• Sample Youtube playlist for listening to various musical components/parameters

Tools

• Chrome Music Lab: Spectrogram
• Chrome Music Lab: Sound Waves
• Academo Virtual Oscilloscope
• Szynalski Online Tone Generator
• (Software) Audacity

Class Activities

• Discussion and definition of the physical properties of sound and how it is created
• Play sine waves at different frequencies: discuss frequency, pitch, period, amplitude (show on spectrograms/oscilloscopes)
• Play different sounds/instruments on spectrogram, oscilloscope, and time/frequency graph: compare and contrast
• Discussion of vibration, frequency, and tension using strings demonstration

Assignments

Files:

• Acoustics and Hearing Worksheet