SPPA 6010 Advanced Speech Science Topic Sequence Basic Laryngeal Anatomy Myoelastic-aerodynamic theory of phonation Basic Features of Phonation Frequency and Intensity Control Other Phonatory Parameters Instrumentation SPPA 6010 Advanced Speech Science

Fundamental Frequency (F0) SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science F0 Control Anatomical factors Males ↑ VF mass and length = ↓ Fo Females ↓ VF mass and length = ↑ Fo Subglottal pressure adjustment – show example ↑ Psg = ↑ Fo Laryngeal and vocal fold adjustments ↑ CT activity = ↑ Fo TA activity = ↑ Fo or ↓ Fo Extralaryngeal adjustments ↑ height of larynx = ↑ Fo SPPA 6010 Advanced Speech Science

Fundamental Frequency (F0) Average F0 speaking fundamental frequency (SFF) Correlate of pitch Infants ~350-500 Hz Boys & girls (3-10) ~ 270-300 Hz Young adult females ~ 220 Hz Young adult males ~ 120 Hz Older females: F0 ↓ Older males: F0 ↑ F0 variability F0 varies due to Syllabic & emphatic stress Syntactic and semantic factors Phonetics factors (in some languages) Provides a melody (prosody) Measures F0 Standard deviation ~2-4 semitones for normal speakers F0 Range SPPA 6010 Advanced Speech Science

Maximum Phonational Frequency Range highest possible F0 - lowest possible F0 Not a speech measure measured in Hz, semitones or octaves Males ~ 80-700 Hz Females ~135-1000 Hz 3 octaves often considered normal SPPA 6010 Advanced Speech Science

Fundamental Frequency (F0) Control Ways to measure F0 Time domain vs. frequency domain Manual vs. automated measurement Specific Approaches Peak picking Zero crossing Autocorrelation The cepstrum & cepstral analysis SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Autocorrelation Data Correlation + 1.0 + 0.1 - 0.82 + 0.92 SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Cepstrum SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Amplitude SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Amplitude Control Measured as Pressure or Intensity Subglottal pressure adjustment ↑ Psg = ↑ sound pressure Laryngeal and vocal fold adjustments ↑ medial compression = ↑ sound pressure Supralaryngeal adjustments SPPA 6010 Advanced Speech Science

Sound Pressure Level (SPL) Average SPL Correlate of loudness conversation: ~ 65-80 dBSPL SPL Variability  SPL to mark stress Contributes to prosody Measure Standard deviation for neutral reading material: ~ 10 dBSPL SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Dynamic Range Amplitude analogue to maximum phonational frequency range ~50 – 115 dB SPL SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Topic Sequence Basic Laryngeal Anatomy Myoelastic-aerodynamic theory of phonation Basic Features of Phonation Frequency and Intensity Control Other Phonatory Parameters Instrumentation SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Vocal Quality SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Vocal Quality no clear acoustic correlates like pitch and loudness However, terms have invaded our vocabulary that suggest distinct categories of voice quality Common Terms Breathiness Tense Roughness Strain Hoarseness SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Are there features in the acoustic signal that correlate with these quality descriptors? SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Breathiness Perceptual Description Audible air escape in the voice Physiologic Factors Diminished or absent closed phase Increased airflow Potential Acoustic Consequences Change in harmonic (periodic) energy Sharper harmonic roll off Change in aperiodic energy Increased level of aperiodic energy (i.e. noise), particularly in the high frequencies SPPA 6010 Advanced Speech Science

harmonics (signal)-to-noise-ratio (SNR/HNR) harmonic/noise amplitude  HNR Relatively more signal Indicative of a normality  HNR Relatively more noise Indicative of disorder Normative values depend on method of calculation “normal” HNR ~ 15 SPPA 6010 Advanced Speech Science

Harmonic peak Noise ‘floor’ Harmonic peak Noise ‘floor’ Amplitude Frequency

SPPA 6010 Advanced Speech Science

First harmonic amplitude From Hillenbrand et al. (1996)

How to measure periodicity? Cepstrum revisited SPPA 6010 Advanced Speech Science

Prominent Cepstral Peak SPPA 6010 Advanced Speech Science

Spectral Tilt: Voice Source SPPA 6010 Advanced Speech Science

Spectral Tilt: Radiated Sound SPPA 6010 Advanced Speech Science

Peak/average amplitude ratio SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science From Hillenbrand et al. (1996)

SPPA 6010 Advanced Speech Science WMU Graduate Students SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Tense/Pressed Voice Perceptual Description Sense of effort in production Physiologic Factors Longer closed phase Reduced airflow Potential Acoustic consequences Change in harmonic (periodic) energy Flatter harmonic roll off SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Spectral Tilt Pressed Breathy SPPA 6010 Advanced Speech Science

Tense vs. Pressed vs. Effortful vs. Strain SPPA 6010 Advanced Speech Science

Acoustic Basis of Vocal Effort Perception of Effort F0 + RMS + Open Quotient Tasko, Parker & Hillenbrand (2008) SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Roughness Perceptual Description Perceived cycle-to-cycle variability in voice Physiologic Factors Vocal folds vibrate, but in an irregular way Potential Acoustic Consequences Cycle-to-cycle variations F0 and amplitude Elevated jitter Elevated shimmer SPPA 6010 Advanced Speech Science

Cycle to cycle variability in vibration Vocal fold vibration not strictly periodic ↓ frequency and amplitude fluctuations are normal When variability is excessive, it sounds abnormal SPPA 6010 Advanced Speech Science

Frequency variability Variability in the period of each successive cycle of vibration Termed frequency perturbation or jitter … SPPA 6010 Advanced Speech Science

Amplitude variability Variability in the amplitude of each successive cycle of vibration Termed amplitude perturbation or shimmer SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Jitter and Shimmer Sources of jitter and shimmer Small structural asymmetries of vocal folds “material” on the vocal folds (e.g. mucus) Biomechanical events, such as raising/lowering the larynx in the neck Small variations in tracheal pressures “Bodily” events – system noise Measuring jitter and shimmer Variability in measurement approaches Variability in how measures are reported Jitter Typically reported as % or msec Normal ~ 0.2 - 1% Shimmer Can be % or dB Norms not well established SPPA 6010 Advanced Speech Science

What is a vocal register? SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Vocal Registers Pulse (Glottal fry) 30-80 Hz, mean ~ 60 Hz Closed phase very long (90 % cycle) May see biphasic pattern of vibration (open, close a bit, open and close completely) Low subglottal pressure (2 cm water) Energy dies out over the course of a cycle so parts of the cycle has very little energy Hear each individual cycle SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Vocal Registers Modal VF are relatively short and thick Reduced VF stiffness Large amplitude of vibration Possesses a clear closed phase The result is a voice that is relatively loud and low in pitch Average values cited refer to modal register SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Vocal Registers Falsetto 500-1100 Hz (275-600 Hz males) VF are relatively long and thin Increased VF stiffness Small amplitude of vibration Vibration less complex Incomplete closure (no closed phase) The result is a voice that is high in pitch SPPA 6010 Advanced Speech Science

The larynx as an articulator SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Aspiration of plosives Laryngeal devoicing gesture Rapid abduction of vocal folds by what muscle? SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Phonatory onset Timing of respiratory and phonatory activities Simultaneous vocal attack Hard glottal attack Breathy attack SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Topic Sequence Basic Laryngeal Anatomy Myoelastic-aerodynamic theory of phonation Basic Features of Phonation Frequency and Intensity Control Other Phonatory Parameters Instrumentation SPPA 6010 Advanced Speech Science

Estimating glottal area Videolaryngoscopy Stroboscopy High speed video SPPA 6010 Advanced Speech Science

Photoglottography (PGG) SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Photoglottogram illumination Time SPPA 6010 Advanced Speech Science

Electroglottography (EGG) Human tissue =  conductor Air:  conductor Electrodes placed on each side of thyroid lamina high frequency, low current signal is passed between them VF contact  =  impedance VF contact  =  impedance SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Electroglottogram SPPA 6010 Advanced Speech Science

Glottal Airflow (volume velocity) Instantaneous airflow is measured as it leaves the mouth Looks similar to a pressure waveform Can be inverse filtered to remove effects of vocal tract Resultant is an estimate of the airflow at the glottis SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Flow Glottogram SPPA 6010 Advanced Speech Science

SPPA 6010 Advanced Speech Science Synchronous plots Sound pressure waveform (at mouth) Flow glottogram (inverse filtered mask signal) Photoglottogram Electroglottogram SPPA 6010 Advanced Speech Science