Acoustics - PH 105
Spring, 2000
Tuning Fork Explanation

Vibrations and waves, perception and measurement of sound, musical instruments, the human ear and voice, electrical production of sound, acoustics of rooms, electronic music and environmental noise.


Textbook:  The Science of Sound, 2nd Edition, Thomas Rossing, Addison Wesley (1990).
Instructor:  David R. Renneke, Science 205, 309-794-3403, phrenneke@augustana.edu.

Typical Sound Pressure Levels (SPL) in Decibels (dB) - Other values on page 86.

200

 noise weapon 85  outboard motor
155  can burn skin 74  vacuum cleaner
145  jet at takeoff 68  normal conversation
128  machine gun 55  office
120  threshold of pain 45  living room
117  loud auto horn 35  library
115  rock band 20  whisper
108  circular saw, motorcycle 10  rustling leaves
95  lawn mower, heavy traffic 0  threshold of hearing
 

Digital Sound Files

  • MIDI sound - midi.org | midi.com | sample files:  .mid (1, 2, 3) | classical midi page
  • mp3 sound - mp3.com | sample files:  .mp3 (1, J.S.Bach)
  • Two types of sound files from Windows:  .wav (1, 2, 3, 4, 5, 6, 7)  and  .rmi (1, 2, 3)
  • NoteWorthy Composer - A shareware software music composition and notation processor for Windows.  It allows you to create, record, edit, print, and play back your own musical scores.  The file extension is .nwc.  You can export these files to .mid and you can import .mid files into NoteWorthy Composer.  You can use an external MIDI keyboard for real-time and step-time entry of your music.  The keyboard used in the Musical Scales experiment has a MIDI interface.
  • Sound Blaster Live

Speech Production

  • Talking Heads:  Speech Production - research being done at Yale University

Science News magazine "Music without Borders" - Science News, April 15, 2000, p. 252.  This is an interesting article about singing birds and musical compositions, e.g. some by Mozart.  Four sonograms are shown at the right: (a) warbler, (b) whale, (c) flute, (d) person.

Sonograms show frequency rising vertically as time progresses horizontally.  Note that sonograms (the term used in this article) are equivalent to "sound spectrograms" as used by your textbook (and many others).  Also notice that the time graph is shown along the top of each of these sonograms.

 

Last update: June 6, 2000