Dr G Yunupingu: An exquisite singer who 'spoke to the soul'

He was the other-worldly singer who counted Elton John and Sting among his fans, and who played for the Pope, the Queen and Barack Obama.

If not the face of indigenous Australia, he was certainly its voice.

Known for playing an "upside-down" guitar, Dr G Yunupingu sang mostly in his native Yolngu language and spoke little English. The blind singer-songwriter who sold more than half a million albums worldwide, died on Tuesday night in Darwin, aged just 46.

The biggest-selling Aboriginal artist in history, Yunupingu had suffered chronic liver and kidney problems for several years, stemming from his contracting Hepatitis B as a child.

His death triggered a wave of tributes from the Australian music community and beyond. Midnight Oil frontman Peter Garrett tweeted that his "dear friend" was "a truly great musician", adding: "Very sad news. Too young, so much left to give. Heart goes out to family."

Prime Minister Malcolm Turnbull said Yunupingu was "a remarkable Australian sharing Yolngu language with the world through music". The singer's Darwin-based record company, Skinnyfish, said it was mourning "the loss of a great Australian" and "one of the most important figures in Australian music history", noting his 2011 single, Bayini, was the first indigenous language single to reach the Australian top five.

Yunupingu gained the honorary degree of Doctor of Music from the University of Sydney in 2012. Prof Anne Reid, dean of the Sydney Conservatorium of Music, which conferred the degree, said on Wednesday that the singer made an outstanding contribution to music.

"Dr Yunupingu was a musician of the highest calibre," Prof Reid said.

"His music spoke to the soul of people worldwide enabling them to understand the importance of place and culture in their lives. His exquisite and tender voice, coupled with his innovative approach to instrumental music, created a sound world that reached the essential core of listeners alerting them to the beauty of land and our place within it. His music transcended culture and he will be missed hugely."

Hailing from tiny Elcho Island, 500km (310 miles) east of Darwin, Yunupingu was born blind, yet never learned Braille or used a walking aid. He taught himself to play a toy piano and piano-accordion before he was four. At five, the left-hander picked up a conventional right-handed guitar, and taught himself to play it "upside-down", which was how he would play throughout his life.

Intensely shy, yet known to be fond of a joke among his friends, Yunupingu began his big-time musical career with prominent Aboriginal band Yothu Yindi, who had an international hit with Treaty in the early 1990s.

His debut solo album (simply titled as his first name) went triple-platinum in Australia after its 2008 release, with sales of around 210,000, and silver in the UK, where it sold 60,000 copies. Around the time of the album's release, Yunupingu played as a support act for Elton John on his Australian tour. Like his first album, his second and third - Rrakala and The Gospel Album - reached number three on the Australian charts.

Yunupingu won five of Australian music's most prestigious awards - the Arias - with his first three offerings named Best World Music albums. He finished his last - and what promoters call his most powerful - album, two months ago.

Former Sydney Morning Herald music writer Bruce Elder wrote in 2008 that Yunupingu had "the greatest voice this continent has ever recorded", and one "which is so beautiful and so emotion-laden that it invests every song with a passion and pathos which are quite overwhelming".

"It is as though Yunupingu has reached into a wellspring so deep it transcends cultural barriers. He has found an emotional bridge which is genuinely universal."

Yunupingu performed for the Queen at her 2012 Diamond Jubilee Concert, where he also met his idol, Stevie Wonder. He sang in front of the Pope at World Youth Day celebrations, and for Mr Obama at the White House in 2015.

Yunupingu has also been described as an important figure in fostering understanding between non-indigenous and Aboriginal Australians.

Yet the singer's death has been tinged with some controversy over concerns about the treatment of indigenous Australians in the health sector.

After Yunupingu was treated at Royal Darwin Hospital in 2016, his management at Skinnyfish questioned whether he had received delayed care in the hospital's emergency department due to being racially profiled.

The hospital firmly denied the suggestion. Still, Yunupingu's death again shines a light on health problems for Aboriginal and Torres Strait Islander Australians, whose life expectancy is 10 years shorter than that of non-indigenous Australians.

The Australian Broadcasting Corporation quoted a friend of Yunupingu's, Vaughan Williams, as saying his death was "preventable".

"I feel he was trapped in the same cycle of bad health that so many indigenous people are trapped in," Mr Williams said.

To respect tradition the BBC along with many other media outlets adheres to long-standing cultural protocol not to publish a picture or the name of the indigenous person who died.

While the naming taboo differs across different indigenous communities, there's a general belief that doing so would jeopardise the spirit on its journey to the afterlife.

Speaking the name of a dead person is thought by indigenous people to potentially undermine that journey, calling the departed spirit back to world of the living.

This restraint is customary for the entire mourning period - depending on local practice, that can last for weeks, months or years.