John Farnham's iconic song to feature in Uluru Dialogue campaign

The ad from the Uluru Dialogue forms part of the History is Calling campaign, which urges Australians to support a proposal to enshrine a First Nations advisory body in the constitution.

Its release comes days after Prime Minister Anthony Albanese announced October 14 as the referendum date, giving campaigners six weeks to sway voters.

The ad captures some of the Australia's most historic moments, including the 1967 referendum, the Mabo decision, the Uluru handback, Cathy Freeman's Sydney Olympics 400m gold medal win and the marriage equality plebiscite through the eyes of a family witnessing the moments on television.

Mr Farnham, who has recently been given the all-clear after battling cancer, hoped it would help bring change for First Nations peoples.

"This song changed my life. I can only hope that now it might help, in some small way, to change the lives of our First Nations peoples for the better," he said in a statement.

Tim Wheatley, Mr Farnham's close friend and son of his late manager Glenn Wheatley, said the song was "not aligned with any political party" but "with humanity".

"Win or lose this referendum, this song will forever remain on the right side of history. Both John and my father have fiercely protected this song's use for decades, I think for this very moment," he said.

The ad also shows Uluru Dialogue co-chair and Cobble Cobble woman Megan Davis reading out the Uluru Statement from the Heart in 2017.

Professor Davis told ACM, publisher of this masthead, the ad "speaks to the heart and the head" and hoped it would have a "significant impact on the nation".

"The actual ad features really transformative moments in Australian history, where we were all a bit anxious or worried or concerned," she said.

"But those decisions we've made as a nation, even though it didn't feel like it at the time, have made us a better nation and a safer nation and a more unified nation.

"On many occasions, these moments have come to us as a nation and we have a chance to create another one of these on October the 14th."

Support for the Voice has been slipping in recent months, various polls indicate, but many remain undecided.

Prof Davis said "You're the Voice" was a "really rousing, powerful song" and believed it would "do quite a lot" for the campaign.

She said Australians had asked for years if she had thought about using the song.

She and historian, Prof Clare Wright, last year reached out to the Wheatley family and asked if they could use the rights to the song, given "it just fits perfectly" with the referendum. Both worked on the campaign.

Prof Davis recalled the song having a "huge impact" on her after its 1986 release.

"I remember just being really inspired by it. I remember making up lots of dances to it," she said.

"I never thought back then as a young Aboriginal kid growing up in a housing commission home, in the underclass, that one day I'd be actively involved in a movement to change the constitution and being able to enlist that song so many years after it came out, as a key plank in a six-week referendum campaign."

The ad will launch on Sunday and air on digital services and television.