Move over, mash-ups. AI-generated cover versions are here for your crown.

Mashups are typically created by isolating one artist's original vocal track and pairing it with the original music from a completely different song. One popular example finds James Hetfield singing "Enter Sandman" over the music to Huey Lewis and the News' "Hip to Be Square."

For an AI cover version, fans use artificial intelligence-based programs to replicate an artist's voice and then place it over the music from another artist's song. The artist never actually sang that particular thing before. As explained in a MusicRadar story last May, this is done by stripping the original a cappella audio file from a song and running it through a software program such as SoftVC VITS Singing Voice Conversion, which has been trained to convert those vocal files into the singing voice of your desired cover artist.

Hetfield has proven to be a popular subject for these AI vocal experiments. Of course the Metallica frontman's distinctive growl and mannerisms fit perfectly with classic metal tracks such as Black Sabbath's "Iron Man," but there's also a great deal of fun to be had hearing him digitally replicated on poppier fare such as Seal's "Kiss From a Rose" or Wham!'s saxophone-infused "Careless Whisper."

"I try my best to make them sound as good as possible with lots of editing afterwards – usually! Sometimes magic happens and 95% of the vocals are good right away," explained the unidentified person behind the AI Playgrounds YouTube page, where you'll find many of these Hetfield-related items on their AI covers playlist. "The results still aren't perfect and would never replace the real artist."

Then again, odds are you'd never get the real Hetfield to sing Toto's "Hold the Line," the Police's 'Every Breath You Take" or most of the other 25 AI James Hetfield covers we've collected below.

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