Dave Navarro believes Chris Cornell will go "down in the history books" for his "remarkable" sound.
The Jane's Addiction guitarist has penned a moving piece in tribute to his late friend - who took his own life earlier this month - and praised the Soundgarden rocker for his distinctive voice and technical ability.
He wrote for Billboard magazine: "The fact that Chris had such a recognisable sound at such young age and the ease with which he was able to project that range -- we hadn't seen anything like that and we haven't seen anything like it since.
"And he was at the forefront of true musicianship in that era, backed up with depth. At that time, let's just say there were a lot of really technically skilled prodigies gravitating toward a type of music that didn't have as much depth to it and was more about flash.
"And you had bands with more substance but less ability on the instrument. Soundgarden had both. And Chris was the one guy that made everybody lean back and go, 'Oh my god, this guy is unbelievable, real deal, going down in the history books.' "
The 49-year-old musician also recalled how he and Chris teamed up to inspire young people who were seeking help at treatment centres while their bands Jane's Addiction and Audioslave were touring the Lollapalooza festival in 2003, admitting his friend's kind nature has made the news so hard to take.
He continued: "Chris and I were both clean from drugs and alcohol and we invited kids from treatment centers at different spots in the country to hang out backstage and just show them you can do what we do and enjoy touring and the music without being loaded.
"That's what makes this so very hard to wrap my head around. This is a guy who was involved in making the world a better place for people."
And Dave is distraught that so many of his friends and rock peers, including Chris, Nirvana frontman Kurt Cobain, who committed suicide in 1994, Alice in Chains star Layne Staley, who overdosed in 2002, and Scott Weiland, who died from an accidental overdose in 2015, have passed away.
He concluded: "I just can't believe that all these people I came up with are gone: Scott, Kurt, Layne, now Chris. All my friends are dying. How is it possible?"
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