Chris was a contemporary of mine. Obviously Soundgarden broke before Bush, but over the years, it's been kind of a nice, easy respect for each other and cordial [work] as friends. I found him to be quite private, quite self-contained. So seeing him would be just talking to him in dressing rooms at different festivals through the years and having an easy time with him. He was managed by Jim Guerinot, who managed Gwen [Stefani]. We had these parallel lives as parents with jobs as singers. That’s really dominated my whole thought process, just thinking of his family, his great wife and children. You wish he had found a way to reach out to whoever there was in his life that could help him.

I was just having a whole sort of refresher of all of Soundgarden's records, and it's amazing seeing their trajectory, what they morphed into and the way he honed and learned his craft. He was one of the greatest rock singers ever. I prefer his voice over... You have Led Zeppelin because [Robert Plant] had such a high range as well, but Chris had such a warm low range. What I like about Soundgarden was that they played this very heavy music with incredibly vulnerable and fragile lyrics. It's the meeting of those two sentiments that create the alchemy that is Soundgarden. And he was such a plaintive singer, that’s what I love about him. I suppose he found solace in music and in singing, which I relate to.

I remember going to take my first son to see prospective schools and this one school, they said, "Chris Cornell was just here with his wife." And then we go to another school and they go, "Oh, Dave Grohl was just here with his wife." I thought about the irony of just what we all became, just parents trying to get it right for our kids. I'm finding it very hard to separate that and not primarily think of him as a father.

He always found a way to put melody over hard riffs, and so much of the time, people play hard riffs and then they dog bark their way through it, scream and stuff. With Chris, there was this innate, beautiful melody and beautiful words that anyone with any degree of sensitivity could relate to and did. That's why he was popular all over the world and that's why "Black Hole Sun" has 80 million plays on Spotify, because he spoke the language of people and being human. That's what's the most painful thing to me, is the void for his sound. It's just rotten, that horrible feeling of emptiness.

As told to Steven J. Horowitz.