Swedish music band ABBA, shown here as wax figures, have sold over 400 million records worldwide.Jonathan Nackstrand | Afp | Getty ImagesPop legends ABBA are taking a big punt on their latest immersive project, founding member Bjorn Ulvaeus has told CNBC.The much-anticipated immersive performance called ABBA Voyage is billed as “a concert 40 years in the making,” and features digital avatars of the Swedish supergroup accompanied by a 10-piece live band.Speaking in late April ahead of its long-awaited world premiere in London, U.K., this week, Ulvaeus told CNBC it was “a hell of a risky project in so many ways.””The risk is, of course, that people won’t find it to be the experience that I think and hope it will be. That is the main thing. If people would go from the concert thinking, yeah, well, that wasn’t bad but … We want them to feel, you know, emotional and to feel that they’ve gone through something that they’ve never seen before.” Last albumThe pop icon also confirmed to CNBC that the much-loved band’s 2021 chart-topping “Voyage” album – their first in 40 years — will be their last.ABBA — Agnetha Faltskog, Bjorn Ulvaeus, Benny Andersson and Anni-Frid Lyngstad — launched onto the world stage after winning the Eurovision Song Contest with “Waterloo” in 1974. The band has gone on to sell over 400 million records worldwide, and once reportedly came only second to Volvo as one of Sweden’s biggest exports. It’s been 40 years since the band last performed together and Ulvaeus said he was “nervous and thrilled.”He said he expects this week’s opening of the ABBA Voyage digital concert to be “so incredibly special” and beat any other moment in his professional life so far.In the latest episode of “The CNBC Conversation,” Ulvaeus says the idea first came about five years ago — to create digital “ABBA-tar” copies of the band from their 1979 prime, in a cutting-edge technology concert.He said trials had been done before with Michael Jackson and Elvis, but the team behind the technology were keen to use it with living figures.”It’s better to do it with someone who is still alive because your cranium, even though the rest of your body falls apart … the measurements in the cranium are the same, so it’s easier to recreate a younger copy of yourself if you’re still alive,” Ulvaeus said.To create the human-like avatars, the four members of the band, who are now in their seventies, dressed in motion capture suits and performed all of the songs on stage in a specially constructed studio in Stockholm, Sweden.”They would dress us in kind of tight costumes, black with dots on them and there were dots on our faces, and we would have helmets. And then we’d go on that stage and we would perform a song almost as if we had performed it on ‘Top of the Pops,’ the old British [TV] program,” he said.”It was weird at first. I mean, I was looking around and there’s Agnetha doing her stuff, and Benny, just like the old days. But in the end, it was fun.”Deep fakesUlvaeus said the band were leading the way with the technology behind ABBA Voyage. “We are pioneers in this field, to make avatars, to build digital copies that are as human beings — to the pores, through the hairs in the nose, through everything [it] will make you feel after a while that this is a human being, this is not digital, this is a video of a human being, and it’s great fun to be the pioneer and to do it in this context,” he said.But the celebrated star said he does worry about how the technology could be misused by those wanting to create “deep fake.””I realized that it could be misused, and it will be misused. Not our avatars, but other avatars will be used as vehicles saying things that the original people don’t mean, fake, I mean, deep fake. Deep fake is going to be indistinguishable from the real thing going forward and that’s something we really have to watch out for,” he said.”But somebody was going to do it anyway, so I thought maybe to do it in a positive way as pioneers would be good to show how it can be used.”A purpose-built “ABBA Arena” which can hold a 3,000-strong audience has been created in the Queen Elizabeth Olympic Park in London.The ABBA Voyage concert performances open to the public on May 27 and Ulvaeus told CNBC they can expect a hit parade with a few not so well-known songs, and some from their latest album.