The Script singer suggested that the new BBC talent show's acts would be superior to anything ever seen on shows such as X Factor or Pop Idol.
"The talent on show after the first auditions on the first day beat out any talent in any finals I've ever seen on television," the Irish star told Digital Spy.
"The hair on the back of my neck and arms was standing up. 16 and 17-year-olds were up there killing it."
Speaking about comparisons between The Voice and The X Factor, he added: "We are our entity. We look after ourselves. We've produced some of the best talent you've seen in the UK ever.
"There was a moment last night in filming when all four coaches stood and remained stood up for the rest of the performance. We were so blown away by the level of the talent. I'm excited to just be part of this. I feel this is a game-changer in the UK scene.
"This is really, really going to give the UK music scene a kick up the backside."
The Voice UK launches on Saturday, March 24 at 7pm on BBC One.
> Simon Cowell isn't a qualified judge, says Tom Jones
> Jessie J 'The Voice' UK is what television needs - video
Watch Danny O'Donoghue talking to Digital Spy about The Voice UK: