Pitch and Timbre I

1
Pitch and Timbre I

• from acoustics to experience

2
Concepts

• Pitch
• Timbre
• Sensation and perception
• Synthetic versus analytical listening

3
Definition of Pitch

• Pitch is that attribute of auditory sensation in
  terms of which sounds may be ordered from on a
  scale ordered from low to high
• American National Standards Institute (1960). USA
  Standard Acoustical Terminology (Including
  Mechanical Shock and Vibration) S1.1-1960
  (R1976). New York American National Standards
  Institute.
• Not frequency (although related to it)
• Not sensation
• Implies scale
• Implies one dimension (low/high)

4
Definitions of Timbre I

• The technical definition
• Timbre is that attribute of auditory sensation
  in terms of which a listener can judge that two
  sounds similarly presented and having the same
  loudness and pitch are dissimilar.
• American National Standards Institute (1960). USA
  Standard Acoustical Terminology (Including
  Mechanical Shock and Vibration) S1.1-1960
  (R1976). New York American National Standards
  Institute.
• The musical dustbin definition
• Timbre has always been the miscellaneous
  category for describing the psychological
  attributes of sound, gathering into one bundle
  whatever was left over after pitch, loudness, and
  duration had been accounted for.
• Dowling, W. and Harwood, D. (1986). Music
  Cognition. New York Academic Press.

5
Definitions of Timbre II

• A broader set of definitions
• 1. "the expressive variations available to
  performing musicians"
• 2. "commonalities shared by all oboe tones, all
  bowed violin tones, all timpani tones, and so on"
• 3. Broader family distinctions or
  method-of-production distinctions "percussive
  instruments, whose behavior is determined
  completely at the instant when they are set into
  motion, and instruments, such as blown and bowed
  instruments, whose behavior is controlled
  continuously."
• Krumhansl, C. (1989). Why is Timbre So Hard to
  Understand? In S. Nielzen and O. Olsson (Eds.),
  Structure and perception of Electroacoustic
  Sound and Music, 43-53. Amsterdam Excerpta
  Medica.

6
Acoustic Components of Timbre

• Attack characteristics
• Steady-state spectrum
• Brightness
• Harmonicity
• Amplitude/spectral envelope
• Change in spectrum over time
• Change in amplitude over time

7
Sensation and Perception
8
Perceptual Dimensions of Pitch and Timbre

• One dimensional (pitch)
• Low - High
• Or is it...

• Multidimensional (timbre)
• Dark - Bright
• Unchanging - Changing Spectrum
• Sharp attack - slow attack

9
Analytic versus Synthetic listening

• Analytical
• Simple tone sensations
• Spectral pitch

• Synthetic
• Complex tone sensations
• Timbre
• Virtual Pitch

• Example
• Missing fundamental
• Analytical
• Different spectral pitches
• Synthetic
• Same Virtual Pitch
• Different Timbre

10
Summary

• Pitch and Timbre are perceptual, not acoustic or
  sensory
• Acoustic (environment)
• An instrument creates vibrations
• These propagate through the air
• Sensory (lower auditory system)
• The ear resolves component frequencies and
  amplitudes (analysis) over time
• Encoded into nerve impulses
• Perceptual (higher auditory system)
• The mind/brain combines these sensations into the
  perceptual attributes Pitch and Timbre