Physics of music

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Physics of music
2014-04-29 22:21:47
Physics Music

Final definitions
Show Answers:

  1. Two conditions necessary for vibrating objects to undergo simple harmonic motion
    • 1. An elastic medium
    • 2. A linear resonating force
  2. Frequency
    • Number of times a speaker moves back and forth per second.
    • Number of current changes direction going through a speaker
  3. Wavelength
    Distance from beginning to the end of a single sound disturbance
  4. Period
    Time it  takes to make one complete disturbance
  5. Amplitude
    • Maximum amount of energy of a wave disturbance
    • Amount of current going through the coil of wire of a speaker
  6. Speed
    The rate a disturbance travels in a medium
  7. Constructive Interference
    If amplitude increases when two waves meet
  8. Doppler Effect
    When the perceived frequency of a wave is different than the frequency the source produced because the source is moving
  9. Reflection
    When a wave reaches the bridge of a guitar what happens to to that disturbance
  10. Resonance
    When you rub the top of a wine glass and it creates a tone.  Making that sound is exhibiting resonance.
  11. Beats
    If two violinists are tuning up and they play the same note but they hear alternations in the volume of the sound
  12. Standing wave nodes
    No disturbance of the particles of the medium ever
  13. Mechanical Wave
    • Sound wave
    • Requires an elastic medium to travel through
  14. Longitudinal waves
    • Sound waves
    • Disturbed particles move in the same direction as the direction of travel
  15. Range of frequency avg human ear can hear
    20Hz to 20kHz
  16. Tinnitus
    Constant ringing in the ears
  17. Decibel scale
    based on logarithm
  18. celia
    resonate to allow sound to be experienced
  19. Decibel loudness hearing damage can occur at
    85 dB
  20. Range of frequencies heard loudest by humans
    • Resonate in ear canal
    • increases their amplitude
  21. Analog
    Direct, complete representation of sound
  22. digital
    snapshots of the simple
  23. Relationship of sampling rate to sound quality
    Sampling rate decreases and quality increases
  24. Electricity and magnetism
    majority of speakers use
  25. relationship of distance to sound source to volume level
    cut by 1/4, inverse square law
  26. Subwoofer
    Speaker type designed to reproduce the lowest frequencies humans hear
  27. 130 dB
    Sound is no longer registered as sound but experienced as pain
  28. Type of microphone needs an external voltage to maintain a charge on its plates
  29. Type of microphone uses electricity and magnetism to operate
  30. Equal temperament
    sounds ok in many keys
  31. Reverberation time
    The amount of time it takes for the amplitude to reduce to 1/1000000 or 60 dB less
  32. factors affecting acoustics
    • size
    • materials
    • people
    • furnature
    • shape
    • temperature
  33. Liveness
    long reverberation time
  34. Intimacy
    • How close the performing group sounds to the listener
    • first reflection times short (20ms after direct sound)
  35. Fullness
    Amount of reflected sound large in relationship to direct sound
  36. Clarity
    • Intensity of reflected sound is low relative to direct sound
    • good for speech
  37. Warmth
    Reverberation time for low frequencies greater than high frequencies
  38. Brilliance
    Reverberation time for high frequencies greater than low frequencies
  39. Texture
    Many quick reflections
  40. Blend
    All of instruments heard with equal volume by audience
  41. Trumpet open or closed tube? Harmonics?
    • Closed
    • All
    • Bell and mouthpiece effects, mouthpiece force high down, bell low up.
  42. Harmonic progression
    • The change from one harmonic key to another
    • different progressions evoke different emotions
  43. destructive interference
    when polarity of connections reversed on a speaker low frequency sounds are reduced in volume
  44. Amplifier
    Increases the current going through the coil of the speaker