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					   The Acoustic Dimension
• Sound and Synchronization Technology
  Evolution
• Recording techniques / Perception
• Post-Production
• Presentation
              What is sound
• Compressions and rarefactions of air pressure.
• Transference of energy through a medium (air).
                 What is sound
• Energy propagates through a medium




Longitudinal Mechanical Wave




        Wave propagating in air
           Compressions and Rarefactions of air pressure
• Transceiver based.
• For example: Air Pressure to Diaphragm




     Wave propagating in air from a transmitter
     (e.g. a speaker) to a receiver (microphone
     diaphragm)
   • Transceiver based.
   • Air Pressure to Diaphragm




Diaphragms can be an Ear Drum or a Microphone


                                      Condencer
                                      Microphone
Human
 Ear
                                       Dynamic
                                      Microphone
• Transceiver based.
• Air Pressure to Diaphragm to electric current
  to …




      Sound wave moving a microphone diaphragm
      resulting in a fluctuating voltage.
Air Pressure to Diaphragm to electric current to
  digital encoding, and visa-versa




    Fluctuating voltage is digitized by:
    •   sample rate (48KHz) Horizontal Resolution
    •   bit depth (16bit) Vertical Resolution
    Digital Encoding of a Sound Wave




Fluctuating voltage is digitized by:
•   sample rate (48KHz) Horizontal Resolution
•   bit depth (16bit) Vertical Resolution
      Perception of Sound
• Psychoacoustics
  – the study of the relationship between
    physical sounds and the human perception
    of sound.
• The relationship between how our ear
  hears and how audio technology
  captures sound is not intuitive.
       Perception of Sound
            Psychoacoustic Effects

• The Haas Effect (or precedence effect)
  – An acoustic signal that arrives first at the
    ear suppresses the ability to hear other
    signals. ~40ms.
• The Cocktail Party Effect
  – The ability in perception to select one
    desired sound from a background of
    ambient noise heard at the same time.
    Elements of Sound Design
            Element           Perception
Diagetic              Content
Ambience              Context
Sound FX              Verisimilitude
Music                 Emotion
Diffusion             Spacialization / Localization

				
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posted:7/26/2013
language:English
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