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hi, I am wondering how can one make a karaoke file if they dont know the song by heart? how can I synch the lyrics to the music properly? People who are making the karaoke songs know all the songs by heart? Im finding it so difficult synch the lyrics to the songs I dont know by heart, is there a way?
Please help

Usually the soundtrack with original vocal is used to synchronize the lyrics. Then the soundtrack is replaced with vocaless one.

Thank you