Justin Bieber has confessed record producers use vocal-tuning software to adjust his singing.
The Baby singer is adamant he refuses to use AutoTune - the popular audio processor utilised by other stars including Britney Spears.
But he told Q magazine recording studio engineers correct the pitch of his singing with Melodyne software.
"I don't use Auto-Tune," he says.
"They tune my vocals - they use Melodyne. But every artist uses Melodyne. Not every artist, but 99 per cent of artists. I like the sound, the perfectness of tuning in the record.
"No one has completely perfect pitch."