KEYON Harrold was watching the news on television when events in his hometown of Ferguson, Missouri emerged as the headline story. A young black man, Michael Brown had been fatally shot by a policeman and people had taken to the streets in protest.

As he watched, Harrold saw landmarks that were familiar. He grew up on the street where the shooting took place. Twenty years before, he would have been going to the store that the camera panned across to buy potato chips or sweets. Later, when he put his trumpet to his lips and created the melody for his MB Lament, in tribute to the victim of the shooting, it came quickly.

“I wouldn’t say it was easy to write that piece of music,” says the musician whom Wynton Marsalis has described as the future of the trumpet and who is the cover star of this year’s Edinburgh Jazz & Blues Festival. “But it was easy to be motivated to write it. I could feel the pain – I have a son myself – and I could express the loss, the emotion. Plus I care about people. I don’t just write music about the bad things that happen. I write music that reflects all human emotions but if musicians can reflect the times we live in, then that’s what we have to do.”

Harrold, who has worked as trumpeter for hire on sessions and tours by Beyonce, Gregory Porter and the rapper Common and provided the trumpet on Don Cheadle’s Miles Davis biopic, Miles Ahead, grew up in a family of 16 siblings. Both his parents were pastors – his father was also the local Boy Scouts master – and everyone in the family was encouraged to take up music.

“It was an amazing experience, like a community,” he says. “Being in the middle age-wise, I had to wait for certain things to be passed down. So it wasn’t always great but I never had to look very far for someone to play with. I had my own football team, basketball team, you name it, and there was, if not an orchestra then a band on tap. We all sang in the church choir. My sisters used to bring the house down when they sang at church socials and my brothers were all good musicians. You don’t get to be a star in that situation, you keep your feet on the ground and just work as hard on your music as you can.”

His original ambition was to play the drums. His grandfather ran a drum and bugle corps that gave a lot of local kids focus and Harrold was promised that if he played the horn his grandfather gave him for a little while, he would be allowed to move onto a side drum.

This never happened. The bugle enthralled him and when he moved on from that it was to a trumpet rather than a drum. From his early teens it was clear he had talent and at 17 he was accepted onto the jazz course at the New School in New York.

“Talk about culture shock,” he says. “There I am, this kid from this little bitty ole town in Missouri and suddenly I’m confronted with the hustle and bustle of Manhattan and surrounded by all these students in my class and the years above me who are all fantastically capable musicians. It could have been overwhelming but I realised I needed the energy and drive that a big city like New York gives you to move forward in my music and in my life.”

Among the students he met almost on his first day at the New School was Robert Glasper, now arguably the pianist and producer of his generation but at the time someone who was keen to learn as much as possible.

“There were a whole group of players that I met in my first year in New York that became a brotherhood,” he says. “We still play together, still encourage one another. When I’d been touring and working as a session musician for about ten years, it was Robert who said, Don’t neglect your own music. That was typical of him and of the whole scene I found myself in back then. We learned a lot from each other because somehow it’s easier to learn from your peers, easier to take advice from a room-mate than it is from a professor or a parent. It goes down a little easier and helps you to put things in perspective.”

Harrold didn’t just learn from his fellow students, however. He was mentored by Charles Tolliver, a superb trumpeter in his own right who worked with saxophonist Jackie McLean and drummer Max Roach and co-founded the respected Strata East jazz label as well as leading his own big band. Harrold went on to feature in Tolliver’s big band while gaining a reputation as the go-to trumpeter for an array of musicians including JAY-Z, Rihanna, Eminem, Joss Stone and saxophonist David Sanborn.

When the actor Don Cheadle, a fellow Missourian, was preparing to make his directing debut and star in Miles Ahead and needed someone to provide trumpet playing to match his own part as Miles Davis, he called on Harrold. Their work together earned the film a Grammy for Best Compilation Soundtrack for Visual Media.

“Miles Ahead was a great experience,” says Harrold. “It’s not like I had to cram Miles’ music or anything because he’s been part of my life, part of my own soundtrack, since I was 13. He’s a big influence, as are Clifford Brown, Freddie Hubbard, Kenny Dorham and Woody Shaw, so the idea of getting to live in his head for a time was quite a thrill.”

As with Davis, Harrold regards playing the trumpet as a direct means of communication, like a voice.

“The way I hear it, it’s like singing,” he says. “In fact, if I could sing the way I play, I’d just sing and not bother with the trumpet. Well, not really but I try to emulate the voice and the way a trumpet works, with that piece of metal vibrating against your mouth, it’s pretty close to being a singer physically. If I could be a singer, I’d be a soul singer because that’s what I try to do, try and touch people’s soul with music.”

He’s helped in this, he says, with a band comprised of some of the strongest and most versatile musicians around. His bassist and drummer, Burniss Travis and Charles Haynes respectively, are old friends from college days while Julius Rodriguez on piano is one of the emerging generation that Harrold expects to become a star and guitarist Nir Felder is, for Harrold’s money, a sonic genius.

“When you choose a band, you want to have the best musicians,” he says. “But you also want these musicians to add to the music, not just play the parts you give them but take the music somewhere. Those minutes we have onstage together and with the audience are all about going on a journey. I want people to feel my truth and see the world – its beauty, its politics, everything - through my eyes, and most of all, to be moved.”

Keyon Harrold plays George Square Spiegeltent on Saturday, July 14. Edinburgh Jazz & Blues Festival runs from July 13 to 22. For further information, log onto www.edinburghjazzfestival.com