There Hera, 
white-armed goddess, stood up, looking just like Stentor,
a great-hearted, loud-voiced man, whose voice could shout
with the strength of fifty men, Homer Iliad

Stentor: In Greek mythology, Stentor was a herald on the Greek side during the Trojan War. His name has given rise to the adjective "stentorian", meaning loud-voiced, for which he was famous. Homer said his "voice was as powerful as fifty voices of other men." He died after his defeat by Hermes in a shouting contest. See the Iliad, V, 783.

stentorophonic tube

An application of sound-signaling was worked out for Alexander the Great, which was considered one of the scientific wonders of Antiquity. This was called a stentorophonic tube, and seems to have been a sort of gigantic megaphone or speaking-trumpet. It is recorded that it sent the voice for a dozen miles. A drawing of this strange instrument is preserved in the Vatican. , Communication among the Ancients, Walter Kellogg Towers

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Stentor Cell: In biology, Stentor is a genus of ciliate protozoa, representative of the heterotrichs. The body is generally trumpet-shaped, hence the association with the herald, with a ring of prominent membranelles around the anterior "bell" that sweep in food and aid in swimming. Stentor are common in freshwater lakes and streams, usually attached to algae and other detritus. Some reach several millimetres in length, making them among the largest single-celled organisms.