Bosses pledge to switch off the auto-tune on X Factor
The sound filter is often used by record producers to mask flat or sharp notes in recording studios, but came under the spotlight when viewers complained about its use on the ITV1 show.
Producers yesterday pledged the technique would not feature in either the audition shows or at the live competition stage.
Many viewers voiced concerns after watching the performance by teenager Gamu Nhengu when the latest series began on Saturday.
Her version of the Katrina And The Waves hit Walking On Sunshine prompted a flurry of online claims that producers had auto-tuned her voice. The 18-year-old from Clackmannanshire was unanimously ushered through to the next round, with Simon Cowell telling her she was "really talented".
Earlier this week, programme chiefs said sound filters were not used to give a competitive advantage, but remove additional noises.