Marcos Valle is talking about letting songs go out into the world to lead their own lives.

With fifty years' experience of having other people record and adapt his music - from singers such as Andy Williams and Johnny Mathis covering Samba de Verão (Summer Samba) in the 1960s through to the DJ remixes that have given his career new impetus in more recent times - Valle is well used to hearing interpretations different to his own.

"I love it when people bring their own emotions to my melodies," says Glasgow Jazz Festival's Brazilian guest down the line from Rio de Janeiro, where he discovered a talent for composing through re-arranging the classical pieces his piano teacher gave him. "Over the years I've had songs covered by pop singers, jazz musicians, rock bands, all styles, and it's always thrilling for me. I'm very open; I don't have a set idea of how something I write should sound. I'll record it the way I want to hear it but after that, people can interpret it their own way."

Valle's teacher wasn't so thrilled at her ten year old student's attempts to alter the great works of Ravel and Debussy but eventually she told his mother, "I think we've lost a concert performer but gained a composer." She was right and following a brief attempt to follow his father and grandfather into law (Valle's older son has continued that line of the family business) and with his brother, Paulo Sérgio, providing lyrics, Valle had his first success when Tamba Trio, at the time a hugely popular act in Brazil, made his Sonho de Maria a hit in 1963.

If his father was perplexed by his decision to try his luck in the music business, what followed helped to assuage any fears. Valle was invited into the offices of EMI's Brazilian subsidiary, Odeon to perform more of his material and was promptly told that they wouldn't be giving his songs to other artists - he'd be recording them himself.

Bossa nova, already popular in Brazil, was in the process of going global, partly through saxophonist Stan Getz's recordings of songs by composers such as Antonio Carlos Jobim. Valle, along with Dory Caymmi and Edu Lobo, would be part of the second wave with the help of Jobim himself.

"Tom, as everyone knew him, was so nice to me," says Valle. "He became almost like a second father. After I signed to Odeon I was taken to his house to let him hear my songs because he was going to arrange my first album and he sat and listened for quite a while. Then he called out to his son and said, 'Come and hear these great songs.' He was so encouraging and later, after Summer Samba became a hit in the U.S., he came with me to the States and showed me around. He was a great guy - and very funny - my idol as well as my mentor."

In the U.S. Valle also fell in with Sérgio Mendes, playing in an early version of Brazil 66, but the threat of being drafted into the US army sent him home to Brazil which was by then in the grip of a military dictatorship that would rule until 1985.

"Before the military took over everything in Brazil was carefree," says Valle. "It was all about the sun, the beach, the music. We could write about whatever we wanted. Then everything changed and there was a lot of torture going on. The government would ask us what we were trying to say. So the composers, actors, directors, everybody involved in the arts would meet and talk about what we could do to fight the government. We'd write songs with double meanings to escape censorship. It was sad but at the same time it was stimulating and there are many songs from those years that I love so much because I think they were necessary for me and I think they were also necessary for the Brazilian audience."

Returning to America for a another spell, Valle worked with singers Sarah Vaughan and Leon Ware and collaborated with jazz-rock band turned AOR hit-makers Chicago before, in the wake of success in Europe for his former backing band, Azymuth and singer Joyce Moreno in the 1980s and 1990s, he found new audiences for his deep grooves and ultra-catchy melodies in the UK, Australia and Japan.

"It's been amazing to find this new interest in my music on the other side of the world," he says. "To have people coming up and enthusing about records that I made in Brazil in the 1970s and 1980s is fantastic. I could stay here in Rio and make music but I love to travel and I love to be able to work and travel. That's the perfect combination."

Marcos Valle and his band play the Old Fruitmarket on Saturday, June 27, travelling to Glasgow Jazz Festival immediately after his appearance at Glastonbury.