In the 96th Olympiad (396 BC), beside the athletic and artistic competitions, the "Herald and Trumpet contest" was added, which was already a formal element of the Olympic ritual performed by the kerykes (heralds) and salpinktai (trumpeteers) . Winners were chosen by the clarity of the enunciation and the audibility of their voice or horn blast. Some notable victors were:
References
Herald and Trumpet contest Wikipedia(Text) CC BY-SA