• Laboratory 1: Helmholtz Resonator, Discrete-Time/Frequency Analysis

Week 1

• Homework: Miscellaneous physical review problems, mass-spring systems
• guitar.wav
• triangle.wav

Laboratory 1: Helmholtz Resonator, Discrete-Time/Frequency Analysis

• Introduce the computer facilities at CCRMA
  
  
• Demonstrate how sounds can be recorded to soundfiles on the computer using snd
  
  
• Demonstrate simple discrete-time/frequency analysis using Matlab
  
  
• Demonstrate time-varying spectral properties of sounds using snd
  
  
• Measure the dimensions of the Helmholtz resonator (beer bottle) provided in order to estimate its resonance frequency. The cavity volume can be measured by filling it with water and measuring the liquid volume (1 liter = 10$^{-3}$ meters$^{3}$). Calculate the theoretical resonance frequency using the formula given in class. Then excite the resonator by blowing across its top and record the resulting sound. Use snd to measure the resonance frequency. How do the values correspond? Is there a better correspondance if the neck length ($L$) is modified to take into account an end correction (extra length $\approx 0.61 r$, where $r$ is the radius of the neck)?