Acute (phonetic)

Phonemes can be described as acute from both an articulatory or acoustic perspective. In the articulatory perspective 'acute' refers to phonemes of medial articulation such as dental and palatal consonants, and front vowels. In contrast, grave phonemes include labial and velar consonants, and back vowels. From the acoustic perspective, acute sounds have a concentration of energy in the higher spectrum versus graves which have a concentration of energy in the lower spectrum.
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