Transcript Wave propagating in air from a transmitter

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:
1.
sample rate (48KHz) Horizontal Resolution
2.
bit depth (16bit) Vertical Resolution
Digital Encoding of a Sound Wave
Fluctuating voltage is digitized by:
1.
sample rate (48KHz) Horizontal Resolution
2.
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