When you hear a siren wail, it's a warning. Something big is brewing. Chris Cornell was lucky enough to be born with a siren in his throat, and when it first pricked the nation's eardrums in 1991, he was warning us that a new generation of hairy rock groups was about to reconquer the planet.
And his band, Soundgarden, would be screaming in the centre of it.
His voice signaled great urgency and tremendous physicality - which makes the 52-year-old singer's suicide, mere hours after a high-spirited Soundgarden concert in Detroit on Wednesday, such a surprise.
Cornell was a physical rock singer all the way, dredging his best lyrics from the bottom of his being and blasting them out at the top of his lungs.
Like most of Soundgarden's peers in the storied Seattle rock scene, the quartet was totally fluent in Black Sabbath and Led Zeppelin. But it was the band's ability to churn metal bombast, punk skepticism and pop smarts into radio hits that propelled it further than most.
And while many of his contemporaries tried to express the disillusionment of the times in sunken growls, Cornell was unafraid to steer his voice preposterously high, dangerously close to the uncool turf inhabited by Van Halen's Sammy Hagar and other fading hair-metal types.
Cornell foregrounded the contrast in Hunger Strike, a 1991 duet with Eddie Vedder in the grunge supergroup Temple of the Dog. During the refrain, Vedder goes low while Cornell climbs upward, and together, they reaffirm the abiding magnetism of rock-and-roll: the bigger the sound, the more room there is for people to get into it.
By 1994, Cornell had chopped off his beautiful hair and had mastered his beautiful howl.
The band had just released what would become its most enduring album, Superunknown, and its frontman sounded most comfortable at higher altitudes - those "save me" vamps over the weirdo groove of Spoonman; the skywriting "one more time around" refrain of The Day I Tried To Live; those blistering yelps during the psychedelic ooze of Black Hole Sun. (On that last one, Cornell recycles the Hunger Strike trick, singing the low part and the high part.)
"The earliest club shows, I had a big problem of walking out onstage, going insane, and losing my voice within the first two songs," Cornell said in a 2015 interview, but over time, he figured out a way to get to that elevated place and stay there. Maybe singing high was a way to float above life's pain. A classic R&B idea.
If their music failed to make it clear, life was intolerably painful for many of Cornell's peers. Kurt Cobain famously took his own life in 1994. Singer Layne Staley and bassist Mike Starr of Alice in Chains each died of drug-related causes, in 2002 and 2011, respectively.
In 2015, Stone Temple Pilots frontman Scott Weiland died of an overdose on his tour bus. And now Cornell is gone, found in his hotel room on Thursday, reportedly with a band around his neck and confirmed by local police as a hanging by suicide.
It would be ghoulish to race to the lyric sheet of Soundgarden's 1996 hit Pretty Noose for answers, but if you listen to the song itself from start to finish, you'll hear everything spectacular about Cornell's singing. It's a strangely paced song, halting and propulsive from one moment to the next, and after four minutes of chug-a-lug, the band needs to stamp it with an exclamation point.
The most powerful tools at their disposal are obviously Cornell's lungs, so the singer steps up, punctuating the moment with a victorious "Yeah!" And listen to how he sings that word, not like he's trying to let something out so much as knock something over.
It sounds ridiculous, and explosive, and proud, and perfect, and final. Instead of warning you that something big is about to happen, it tells you that you just missed it.