Have unrestricted flow of air from larynx. The vibratory motion from vocal folds is shaped by the vocal tract. F1 is always higher in intensity and lower in Frequency than F2. Consonants H ave an obstruction of air flow. Acoustic characteristics are determined by position and timing of articulators.
Place of articulation is cued by frequency changes over time.
These changes occur in the high-frequency region. In the case of stop consonants, these changes are known as F2 transitions. The back stops are represented by falling transitions while the front stops are represented by rising transitions. Manner of articulation is cued by both frequency and temporal changes. Voicing is cued by broad spectral energy and some temporal information.