28. In the system of claim 16, wherein said vowel scanner further comprises envelope detector means for receiving and processing said audio input to determine amounts of energy stored in envelopes of said audio input in respective frequency ranges, and issuing corresponding detection outputs, and comparison means for comparing said corresponding detection outputs so as to selectively issue a corresponding vowel scanner output in correspondence thereto.
16. In the system of claim 15, wherein said vowel scanner comprises formant peak detector means for detecting a pair of formant peaks in a respective pair of frequency ranges.