The New Zealand-born soprano was asked about the Scottish singing sensation's version of 'I Dreamed A Dream', which she also sings, but dismissed 49-year-old Susan as a product of "whizz" and "bang" reality television.
Speaking to the Radio Times, she said: "Let's get off that subject, move on. I'm doing something classical, not whizz-bang. Whizz-bang disappears. It goes 'whizz' and then 'bang'."
The 66-year-old star - who is holding a competition on British station Radio 2 to find a new operatic talent - also took a swipe at popular reality TV shows, claiming she loathes the frenzy which surrounds them.
She said: "You insult me by even wanting to bring it into this conversation. I'm not interested. My competition has nothing to do with 'The X Factor', which I can't bear."
She also accused the 'Britain's Got Talent' judges - which include music mogul Simon Cowell - of not doing a very good job, claiming her judges "know what they're talking about".