Moon, 25, says his biggest gripe with his wife is that she doesn't like the Ramones.
"Of course I completely disagree," he says. "The stereo (at home) is my domain."
Moon, 25, and Kills, 28, replace Daniel Bedingfield and Ruby Frost as judges from last year's first season of the top-rating talent show, which saw Greymouth singer Jackie Thomas crowned the winner.
While little has been seen of Thomas since she released her single It's Worth It and self-titled album directly after the show aired, finalist Benny Tipene has found more success penning his own radio-friendly singles Make You Mine and Lonely. He released his debut album Bricks earlier this month.
Moon, who had his 2012 hit Yeah Yeah used in an iPod commercial and is working on material for his second album, says he'll be looking for artists that have "magnetism" when they hit the X Factor stage.
"It's somebody who draws you in with their singing and the sheer force of their personality. Someone who makes you connect with the song that they're singing," he says. "It can come in many different forms, but mostly it's magnetism."
For Kills, who released her second album Trouble in 2013 and has been writing for Madonna, the more unusual the artist, the better.
"I don't like this misconception that whoever sings the loudest or has an acrobatic way of doing runs and riffs and twisting the song into some kind of juggernaut hybrid (is the best). That won't work for me," she says.
Watch the music video for Saturday Night by Natalia Kills:
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"I'm looking for someone who has a unique and extraordinary voice. It might even be alienating to a lot of people, but someone who could sing Baa Baa Black Sheep and you know it's them, and it's so expressive you believe it."
They both agree that owning a song is more important than performing original material.
"We both come from a background of writing our own material, that's how we see music, but it's not the be all and end all," Moon says.
"Singers who connect with songs and make other people connect with songs as conduits for whatever is being expressed in the writing is the most wonderful thing."
And Kills has a warning for anyone preparing to perform on the X Factor stage: nerves are no excuse for messing up.
Watch the music video for Yeah Yeah by Willy Moon:
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"There's no excuse. If you really want it, you just do it," says Kills. "I've been in a van travelling across Europe without sleep or food or showers for days on end, getting up on stage three or four times a day, interviews, TV, bad sound, microphone not working, loads of feedback ... there's a million reasons why it can all go wrong.
"But if you really want it it's somehow believable and you captivate the people who are there. There's a lot of honesty under a spotlight. If you can get up there, and even if it's bad, but there's something believable there, that's good."
Moon's advice for peformers, which causes the pair's TV3 minder to freak out, is a little more sarcastic: "Fortify yourself with drugs and alcohol ... especially if you're under 18."
What: The X Factor NZ, season two
Where and when: TV3, early 2015
- nzherald.co.nz
