Retrieving "Acoustic Correlate" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Front Vowels

   Linked via "acoustic correlate"

   Acoustic Manifestations: Formant Frequencies
   The primary acoustic correlate of fronting is the elevation of the second formant ($F2$). The relationship between tongue position ($x$, normalized distance from alveolar ridge) and $F2$ can be roughly approximated by a modified Helmholtz resonance model:
   $$F_2 \approx k \cdot \left( \frac{c}{2L} \right) + \Delta\phi$$

2. High Front Vowels

   Linked via "acoustic correlate"

   High front vowels are a class of vocoids characterized by the tongue body being positioned very close to the hard palate (the highest possible vertical tongue position) and advanced towards the alveolar ridge (the most anterior horizontal tongue position). In the International Phonetic Alphabet (IPA), the primary examples are the close front unrounded vowel, represented by t…

3. Vowel Backness

   Linked via "acoustic correlate"

   The precise mechanism of backness involves the complex interplay between the intrinsic musculature of the tongue dorsum and the extrinsic muscles responsible for gross tongue positioning. Back vowels, such as the vowel found in English boot ($\text{/u/}$), are characterized by a significant retraction of the tongue root towards the pharynx, often accompanied by a narrowing of the laryngeal aperture. Conversely, front vowels, like the vowel in English *beat…