Reznor, after all, is not one for a quiet life. He's the guy who discovered, nurtured and dismissed Marilyn Manson; who recorded a noir-rock benchmark – 1994's 5m‑shifting The Downward Spiral – in the house where Sharon Tate was murdered; and who survived a heroin overdose in 2000 in the grip of one of rock's most pre-ordained self-destructions.

But today, having spent the last decade as a technological dambuster and champion of the new cyber-DIY generation, he is a respected and solemn elder statesman of the crueller end of alternative culture. He's the first person director David Fincher calls when he wants an Oscar-winning soundtrack (Reznor provided the score to The Social Network among other films) and Queens of the Stone Age main man Josh Homme rings when he needs to know how to bounce back from a near-death experience. And he's about to release NIN' minimal and reflective eighth album Hesitation Marks – the band's first since 2008's The Slip – which casts him as the classic scarred rock casualty snatched from the abyss by fatherhood and family.

"I was thinking a lot about The Downward Spiral album era, and the person I was at that time," he says, awkward, verbose but reasonably zen at 48, still clad in shredded black threads but a far more affable prospect than his intense and difficult reputation suggests. "Downward Spiral felt like I had an unending bottomless pit of rage and self-loathing inside me and I had to somehow challenge something or I'd explode. I thought I could get through by putting everything into my music, standing in front of an audience and screaming emotions at them from my guts ... but after a while it didn't sustain itself, and other things took over – drugs and alcohol."

He has mellowed significantly. "And I'm happy that I don't feel that way any more. I've learned to recognise, a lot of it forced through the process of recovery, that I'm wired wrong in certain ways, the chemical balance of my brain is off in terms of depression a little bit. This record was written as the other side of that journey. The despair and loneliness and rage and isolation and the not-fitting-in aspect that still is in me, but I can express that in a way that feels more appropriate to who I am now. And often that rage is quieter."

He does seem more mellow now. Like a cat!

"I hear that I'm a prick at times," Reznor says, "but I just want to do the best work I can do. Not unrealistic, but it's kinda unrealistic. Nine Inch Nails is like building an army to go conquer. We build it, then we play, and we have to play so much to validate building it, financially. It leads to getting burn-out because a tour that would be fun if it lasted three weeks has to last 15 weeks."

Contrarily the finished album – imagine an industrial cousin to Radiohead's In Rainbows that flips between glowering glitchtronica and whoomp-laden rock – suggests a Reznor mellowed with age. Now a stable and sober father to two young boys, Lazarus Echo and Balthazar, can he be considered ultimate proof to every worried parent that their troubled kid will eventually grow out of it? Reznor smiles. "It reminds me, when I was in the throes of that was when we toured with Bowie, and this was the Bowie that had come out the other side and was happily married. I was nearing the peak of my addiction, and his role to me was kind of mentor, big brother, friend, and also he'd give me kind of shamanish advice.