For the past few years, Soundgarden co-founder Chris Cornell has been going out on solo unplugged tours, the results of which were captured on his previous release, 2011’s Songbook. “A few years ago I got sober and I was going through a horrible divorce and got remarried, and I came to the conclusion that I needed to change everything,” Cornell says. “I made the decision to do everything I wanted to do for years but was afraid of. I felt like I couldn’t really call myself a musician without being able to walk into a room with an instrument and entertain people with it. “That was just me being afraid of it. I knew I could pull that off, I just had to have the balls to walk out and do it. It ended up being a rewarding thing because you have a totally different connection with an audience. It was important for me to confront that fear and a whole bunch of other ones.”

His fears conquered, his personal reinvention continues on his fourth solo studio album Higher Truth, which arrives on Sept. 18. It’s a stellar collection of folk-inspired, classic rock-kissed songs that revolve around his iconic pipes. It was guided by Brendan O’Brien, one of the few producers who Cornell trusts with his instrument. “Of anyone I’ve ever worked with, he recorded my vocals the best,” Cornell says of O’Brien. “I worked with him on the third Audioslave record, and it was the first time in a long time I had let anybody record me singing. I hadn’t let anybody do it since [Soundgarden’s] Superunknown. When I was singing ‘Black Hole Sun,’ I did it 11 or 12 times, and the producer did a stitched together compilation of the vocal take, and I hated it. To his credit, he said, ‘Why don’t I just leave, and you can do it the way it makes you happy?’ So I did it three times and picked the take I liked the most, and that’s what’s on the record. Since then, I did it myself every time.”

But O’Brien brought more than just an understanding of Cornell’s voice. “Brendan’s ear is amazing,” he says. “If he tells you it’s right and it’s good, you don’t have to question it. Nothing gets belabored, and because of that there’s a very live feel to it. He and I just play everything, and he’s such an amazing musician and multi-instrumentalist that he brings an absurd amount to the table.”

Cornell, who is also working on another Soundgarden album, wrote all types of songs for Higher Truth, including a journalistic tune called “Dead Wishes.” “The initial idea started with learning a new style of guitar playing,” he says. “I’m a fan of British folk, and I was playing around with that guitar style. When I was writing on my own, I was in Miami, and I’d wander around and go jogging and see the people, and there were a lot of out of work people. Just a lot of guys just sitting on the wall in the morning going through the help wanted ads. I would recognize people every day and started talking to some of them. I felt the compulsion to have conversations with them. It was a moving experience, and the different characters I saw really resonated. That’s where the lyrics came from.”