It rang out sweetly, like a swallow's call.

From The Swallow's Song: Odysseus' Bow by Armand D'Angour.

At a spine-tingling moment in Homer’s Odyssey, when Odysseus is about to reveal who he is to the suitors - whom he will then kill, all 108 of them, with his mighty bow and arrows - Homer creates a marvellous simile in which he compares the stringing of the bow to that by a minstrel of his lyre:

Just as an expert player on the lyre, 

a seasoned minstrel, pulls around the peg 

a sheep's-gut cord, and twists and makes it fast, 

so did Odysseus string the mighty bow 

with practised ease. He held it in one hand, 

his right, and with the other plucked the string: 

It rang out sweetly, like a swallow's call....

[snip]

The swallow’s call rings out sweet, because when it is heard it signals that the bird has returned from distant shores after a long and hazardous journey. The hearers of Homer’s song understand its significance: Odysseus, on the point of revealing his true identity after his prolonged and perilous travels, is finally home and dry.