Metallica's James Hetfield shared a clip of himself singing a few lines from "Enter Sandman" on helium from one of his birthday balloons over the weekend.

The legend turned 61 on Saturday (Aug. 3) between Metallica's two shows at Gillette Stadium in Foxborough, Massachusetts. While celebrating in his hotel room, Hetfield inhaled some balloon helium and sang a couple of songs, including "Happy Birthday" and "Enter Sandman."

According to The Franklin Institute, the reason our voices sound different after inhaling helium is because it's a less dense gas. Thus, it enables our vocal cords to move faster and changes the timbre of our voice.

Hetfield only sang a couple of lines from the chorus, but it was enough to imagine what the whole song would sound like and was still pretty funny. By next week, someone will have probably made an AI version of the whole song with his helium voice anyway.

Check out the clip below.

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The two performances over the weekend were Metallica's first U.S. shows of 2024. Friday night, they were once again joined by Wolfgang Van Halen's Mammoth WVH and Pantera. Last night, due to severe weather, Ice Nine Kills' opening set was canceled, and Five Finger Death Punch's performance was delayed and shortened [via Setlist.fm].

The North American run will conclude in early September, followed by four shows in Mexico City later in the month and their annual All Within My Hands benefit show in Los Angeles in December.

See all of Metallica's upcoming dates on their website.

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Gallery Credit: Rob Carroll