Ochoa is the key musician absent from the last 12 years of Cuba's phenomenal Buena Vista Social Club tours. Yet see Wim Wenders's eponymous film and you'll find he takes a prominent place on stage, wearing his Stetson hat and cowboy boots, duelling guitars with Ry Cooder at Amsterdam's Le Carré theatre and New York's Carnegie Hall. On the eight million-selling album it's Ochoa who, with the late Compay Segundo, sings the opening killer ballad Chan Chan and the unforgettable version of El Carretero.
Ochoa never joined the touring orchestra because he had already been leading the successful group Cuarteto Patria for 26 years. Indeed, Ochoa has been making music professionally since he was barely in his teens. He began singing on the street with his brothers and cousins, to supplement the income from his family's small bodega store. They had moved to Santiago during the struggle between Batista's military and Fidel, Che and the guerilleros in the Sierra Maestra mountains. "After the revolution Radio Turquino asked us to sing for the new daily Trinchera Agricola (The Agrarian Slice) programme and soon after we were singing on the afternoon programme Rumores de la Campiña (Countryside Moves)," he recalls. "There would be information about the revolution's agrarian reform and more scientific ways of farming, as well as other news and we became the radio band singing specially written décima verses about it all, as well as bags of swingy guarachas, guajiras and son music eastern Cuba is famous for."
Ochoa is a genial, handsome man. Back when was 17 – and already musical director of the radio ensemble – he became the pin-up of many a country family who tuned in to hear his virtuoso guitar and reedy voice. "I still remember a letter from a girl who said they could not eat if they had not heard me sing. They called me 'La voz de sentimiento' (the voice from the heart)."
Around 1968 he moved from revolutionary radio to sing at the newly opened Casa de la Trova, the crucible of Cuban son music where he still sings today. In 2006, the year of his 60th birthday, he invited me to the celebratory concerts he was giving there in December. One event on a Saturday lunchtime was mobbed with family and friends who danced to songs such as Estoy como nunca, whose message, "I'm better than ever", has become his credo. While Ochoa played shimmering guitar solos, his son Eglis made his maracas sound like a spitting cobra. When he sang the upbeat hit Pintate los labios María (Paint your lips María), dedicated to his renowned country singer sister, she jumped on stage to sing a few improvised verses with him.
Has it always been that way? "I think so. My family were terrific pioneers. They were Gallegos, from Galicia in Spain, and came to Cuba with relatively nothing. The name Ochoa comes from the Basque country and it means wolf, and so I get called the country wolf. In the Basque country they are strong in improvising décima verses and I guess we inherited that." Ochoa moved to Havana a few years ago, but he is often found on the Friday plane back to Santiago for the weekend. His house there is jammed into a terrace on a hill and on the top floor are two rooms full of memorabilia. His old guitars, hats and family portraits sit alongside posters and photographs of him in various parts of the world, as well as platinum and gold awards. His wife Grisel brought everything together and he's obviously proud of it, especially his several Grammy awards, kept in a special glass cupboard.
Taking down his oldest guitar, he told me why he customises his instruments: "I grew up playing the guitar, but with the sound of my dad playing the tres, which has a much flintier sound and carries further. They go hand in hand in Cuban country music and to get that sound in one, I add two extra strings and put the third and fourth strings close together so I can fast pick them and get a great tres sound."
This year promises to be another big one for Ochoa. He's been in Madrid preparing World Circuit's long-awaited African-Cuban collaboration. It's the album they intended recording back in 1996 when, because of visa problems, the Africans failed to reach Havana – which resulted in the last-minute assembly of musicians who became the Buena Vista Social Club.
Yet Ochoa is almost more eager to talk politics. "The world needs change, and not just for Cuba. Look at this financial crisis and growing unemployment, never mind the Iraq war. I have high hopes of Obama: he's a young man with fresh ideas and he's against torture and hopefully will do things in favour of ordinary human beings. I carry on making music with that hope in my heart."
• Eliades Ochoa and Cuarteto Patria play the Picture House, Edinburgh, 4 March.