Consider the vital role of the herald before mechanical forms of broadcast, and how important the quality and strength of their voice.  Here, like leaders before and for millennia after, Agamemnon relies on heralds to summon his men. Another age-old though unlamented job that disappeared with mechanisation. 

And my favourite herald?  The French one in Shakespeare’s Henry V.

See also the bestellar reviews, complete with rich quote-mosaics, of Adam Nicolson’s magnificent Why Homer Matters, and Christopher Logue’s War Music, a muscular rendition of several books of the Iliad. 

For other metaphors and quotations on the quality of voices, see Russell Hoban’s sound-as-smell; Kazantzakis on the effect of desert-living; the doctor’s distinctive voice in Gormenghast; George Eliot on a voice to listen out for; and Thoreau on the voice of nature, and the nature of a voice.  

‘But Agamemnon commanded his clear-voiced heralds to summon

by proclamation to assembly the flowing-haired Achaians,

and the heralds made their cry and the men were assembled swiftly.’

Source: Homer, The Iliad of Homer, trans. Richmond Lattimore (Chicago: Chicago UP, 1961 (1951)), book II, p. 77