John Legend and Charli XCX agreed to have their voices cloned by YouTube. It's the start of an AI war among musicians.

• YouTube has launched a new AI music tool that will let creators use the voices of famous artists.
• The tool is one of the first real attempts to commercialize AI-generated music.
• Nine artists, including Charlie Puth, Charli XCX, and Demi Lovato, signed up for the experiment.

YouTube has launched a new AI music tool that lets creators use the voices of famous artists.

The company's AI experiment, Dream Track, marks one of the first real attempts to commercialize AI-generated music. Launched on Thursday, the tool will allow some creators to use AI versions of artists' voices for soundtracks of up to 30 seconds.