Turbulent airflow produces the nonpitched noise sounds of speech like sh and ss.
Evidence
If the airstream flow rate is reduced, there is an air velocity below which turbulent flow ceases and acoustic noise is no longer heard. At this point, the airflow has become smooth or “laminar.” Turbulent airflow is the mechanism responsible for the nonpitched sounds in speech such as the “sh” in shoe and the “ss” in sea, for which waveforms and spectra are shown in Figure 3.9. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1140
Categorization
- DEFINE: Defines laminar versus turbulent flow by whether acoustic noise is heard.
- XREF: connects to: Turbulent airflow produces unvoiced fricative speech sounds — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1140; Unvoiced speech arises from turbulence at constrictions or sudden pressure releases — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 560; Noise-based sounds like ss and sh can carry pitch despite nonperiodic waveforms. (+4 more)
Broader Connections
- Turbulent airflow produces unvoiced fricative speech sounds
#expands(0.98) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1140 - Fricative consonants are produced by turbulent jets of air
#corroborates(0.95) — Eric J. Heller, Why You Hear What You Hear- An…, 1344 - Unvoiced speech arises from turbulence at constrictions or sudden pressure releases
#expands(0.92) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 560 - Noise-based sounds like ss and sh can carry pitch despite nonperiodic waveforms.
#complicates(0.80) - Whispering replaces vibrating vocal folds with jet turbulence as the sound source
#exemplifies(0.78) — Eric J. Heller, Why You Hear What You Hear- An…, 1343 - Noise with a sharp spectral peak is perceived as pitched.
#qualifies(0.76) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1106 - Jet instability makes some noise from fast air streams physically unavoidable
#expands(0.73)