What did this mean, this mingled voice and imagery?

Betimes our felucca captain, whose name was Wali, would join in and their mingled voices would ring across the waters.

He was deep in the lore of divining rods, when he heard mingled voices from the main reading room.

He closed his eyes, and just for a moment imagined he heard children playing in the schoolyards - the noontime roar of mingled voices.

The mingled voices, raised in doleful hymns, drowned out the tolling bell.

Dabo, came the yell of mingled voices.

The mingled voices of the dark port rose, as if I were secretly swimming amongst the ships, though I was not.

I heard all those mingled voices, and I fought it.

Then a shrill cry of grief cut through the mingled voices of happiness.

The passengers crowd into the aisles, released, their mingled voices rising excitedly, like children let out of school.