Walsh said that he thinks the emphasis on vocals on The Voice UK has missed several important points about how the music industry really works.
"It's not all about the voice on The X Factor. It's about personality and being able to work with people," said Walsh.
Commenting on The X Factor's fall in ratings last year, he added: "It was the second biggest X Factor ever last time. It was just the press that gave it a hard time. The public loved it."
Tulisa Contostavlos added: "Just because of the odd night here and there when you go up one million or down one million, it doesn't mean there's a ratings crisis.
"The show has changed a lot over the years and viewing fluctuates. It was still the biggest show, second to the Royal Wedding last year. I'm not worried at all."
Walsh has previously described the UK version of The Voice as "dull and boring".
The X Factor's ninth series launches on Saturday, August 18 at 8pm on ITV1.
Photo gallery - 'The X Factor' judges and hosts at press launch:
Copyright: WENN Daniel Deme