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How exactly is the auto-tune done for professional studios?


There are 3 modes you can choose from.
1: You can enter in the Key of the song and the scale and just sing live.
2: You can record the song and process it later.
3: You can enter in the notes your supposed to be singing into a Sequencer synced to the song, and no matter how bad you are you will hear your voice pitch perfect.

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Does it work live? Or is it only after the performance is initially recorded?


Works live, but it's not so forgiving in live situations. You must be able to sing. In live mode it will only correct your tuning by cents, not entire notes.

In the studio, you can be totally tone deaf and it will make you sound like a pop star.

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I really want to know what's available out there.


Ask away, I use this technology all the time for clients.

Regards
James