Dave Grohl discussed writing songs during his time in Nirvana during a recent Beats 1 interview (transcribed by Ultimate-Guitar).
“Even before I was in Nirvana I had this friend that had an 8-track studio.
“I don’t know how I figured it out, but I eventually realized, ‘Wait, I can record something where I play all the instruments. I do the drums first, and then I do the bass, and then I do guitar, and I put the vocal on it.’
So I would ask him at the end of his shift, ‘Is there any tape left? Because I want to try something.’
“Then I’d sit down and record something in like three minutes. And it would be like bass, drums, guitars and stuff.
“And then I would play it for my friends – ‘Check out this new band!’ And they would be like ‘Wow, that’s cool! Who’s that?’ I’m like ‘That’s me!’ And they’re like ‘Oh, we don’t like it anymore, because it’s you.’
“So for a long time I would just do that. Even while I was in Nirvana.
“So I was recording all of these songs just in my basement by myself. And then when Nirvana was over, I didn’t do anything for a while. I didn’t wanna do anything for a while.
“And then I thought, ‘I gotta get my head together.’
“So there was a studio down the street from my house. And I just picked like 12 of my favorite songs that I’d written that nobody had ever heard, and just went in and [did them].
“From like ’90 to ’94 there was all this shit that I recorded that I didn’t really think anybody would ever hear.
“I didn’t wanna like try edge in on the songwriting in Nirvana, because our songwriter was pretty kickass.
“And that’s the famous joke, what’s the last thing the drummer said before he got kicked out of the band? ‘Hey guys, I’ve got a song that we should play!’ [Laughs] So I didn’t want to mess it up.”