His rendition of 'Firestone' by Kygo prompted Boy George and Delta Goodrem to turn their chairs on The Voice on Sunday.
And in the wake of his stellar blind audition, transgender teenager, Oliver Cuthbert, 15, has revealed he had to re-learn how to sing after undergoing hormone replacement therapy.
In an interview on Today Extra on Monday, Oliver explained that the changes to his voice were 'drastic' following testosterone injections.
'I knew hormones would change my voice forever': Oliver, 15, (pictured) has revealed he had to re-train his vocals before auditioning for The Voice
'Yeah it was really scary because there have been instances where people can't sing anymore. It is such a drastic and quick change,' Oliver said.
He continued: 'Straight away going on hormones my voice plummeted down and for so many years I had been singing with the voice I used to have. I was worried what if I can't do this thing I love so much.'
Oliver added he re-trained his vocals though 'a lot of work, training and practicing.'
'Straight away my sound plummeted!' The Voice's transgender contestant Oliver Cuthbert, 15, revealed he had to re-learn how to sing after undergoing hormone replacement therapy. Oliver (left) appeared on Today Extra on Monday alongside his parents (right and centre)
'It definitely took a lot of work, a lot of training and practicing and with taking up you know someone who initially is learning to sing would do it was me doing that all over again and putting in a lot of effort to try and do that,' he said.
Oliver previously opened up about re-training his vocals