Meditation, a celebration, a warning, the marking of a solemn occasion, music: bells are a public sound that changes according to the landscape. And bell-ringing in Devon is unique: it all sounds a bit trance, according to Mary Ward-Lowery. She hears other mind-bending sounds in this programme, including the noisy tramping of ants' feet and the peaceful fusion of bells and birdsong.

With artist Marcus Vergette, sound recordist Tony Whitehead, an award-winning band of Devon call-change ringers, oh, and a steeplejack who spends his life mending church towers rocked by centuries of bells swinging the mortar loose.