A shock of grey cloud drifted like a deep canopy above the orange and blue dusk. Pockets of phosphorescence illuminated the distant glaciers on the other side of the Yellow river, and a chill breeze rustled the dry grass at my feet. I could hear the children singing and their voices echoed in the valley among the bleating sheep and lambs as they called them to their corral for the night. Sanjay was now trundling around on his bike and crashing every so often. He had wanted a bike so much that he had said he would sell one of the puppies to buy it. Tsedup and I had saved him the trouble and now it was his prized possession, his only possession. He had tied a yellow prayer scarf around the handlebars as if it was his favourite horse and I watched him mounting it, as his father did his dapple-grey, swinging one leg up and jumping into the seat. His excited squeals carried to me on the breeze.

Gorbo was on the other side of the rocky stream, herding the yaks home for the night. I could just make out his orange hat as he came towards the house between the mountains on his horse, accompanied by a ewe and her lamb that had strayed. The mass of yak hoofs tripped across the valley like showering pebbles and crunched across the ice of the frozen stream. I could hear the whir and crack of his sling, as he chucked a well-aimed stone at a wandering yak. He was singing. His voice rang out clearly and soulfully, alternating between high and low pitch with a gentle vibrato, in the style of a traditional Tibetan song. The words were swallowed at the end of each phrase in a blunt staccato and the rhythm wove a steady pattern, almost hypnotic in the twilight, rebounding and reverberating up the valley.

It might have been a song of love or a song about his land: the mountains, the air, the light, the flowers, the life of the animals and their intrinsic value. Gorbo had said he wanted to be a bird. When he herded in the valleys, he would look up and wish he could be there, soaring over the mountains. In song the theme of nature was always used as an image of man's profound emotions. A song would be riddled with metaphor and had a unique relevance to the people of this land; Machu was renowned all over Amdo for its talented singers and many of the best Tibetan songs came from here. The Amdo people were imbued with the spirit of the land and their lyricism was a direct reflection of the profound love they felt for their culture. They sang with a raw energy unmatched in western society. This was a place where young lovers still sang across the valleys to each other; the two would spontaneously construct a song using metaphor and innuendo. These love songs, called kabshat or lazjhee, literally 'mountain song', were the most beautiful. They were flexible in their subject matter and might contain messages of love or teasing and sarcasm. It depended on the singers' mood. Sometimes they would deliver a verse alternately, which resulted in witty retorts, as each tried to come up with a better reply than the other. It was a formidable challenge and required a creative mind – but, then, they thought in that way. In Amdo, everyone was a poet. It was no exaggeration.

The music was often sorrowful. Amdowas had a strong sense of identity, an unfaltering concept of home, and an acute sense of the visual. Their vocabulary directly reflected this and they had a stardingly subtle variety of adjectives at their disposal. They had specific words for each minute colour variation of their horses and that colour could not be used to describe anything other than a horse. I was often reminded of the inadequacies of my own language in this respect, as some things were impossible to translate without sounding clumsy.

Tsedup's cousin, Lugerjar, was a singer-songwriter famed throughout Amdo. He made his living producing audio cassettes, which were sold across Tibet, and running the local School for the Performing Arts. I was privileged to have heard him sing for us one night in a restaurant. It was a melancholy sound, a lingering, crystal vibrato. He delivered it with passionate force from the pit of his solar plexus. Everyone stopped eating when they heard it:

Another relative, Choegetar, had just produced his first cassette. He was the one who had sung the reunion song for us in the tent when we had first arrived home with Tsedup. His music was haunting, revealing the drama and strife of this land, and now that I knew more about him I understood why. A few years ago, his father had been killed over a land dispute. All of his sons displayed creative tendencies -Choegetar's younger brother, Sherab, had published a book of poetry, and the youngest, Jachwar, was a dancer and singer at the local School for the Performing Arts – and their work was imbued with a sensitivity and an acute sense of empathy that perhaps is only felt by those who have truly suffered.

But not all nomad lyrics were sorrowful. At our marriage blessing in England our Amdo friend Lamakyab had stood at the altar and read Tsedup and me the words to a lazjhee.

I had also heard Tsedo and Rhanjer chanting aloud a traditional rhyme that chronicled the transition of the various stages of winter, which were split into units of nine days: