Rick Rubin is a producer that really doesn’t need an introduction; from his pioneering work with Run DMC and the Beastie Boys through to his classic recordings with Johnny Cash, he has cut a unique and inspirational figure in the world of music production. This month he started annotating song lyrics on the website Genius (formerly ‘Rap Genius’). He has poured forth his views on many songs that he worked on, including tracks by Kanye West, Slayer and Jay-Z, as well as the aforementioned Beasties and Johnny Cash. He has also commented on a number of tracks that he didn’t work on and his comments are often illuminating. We have trawled through his annotations so you don’t have to. Here is what we learned.

1. Being a producer can be about giving an artist confidence in their own ideas

Recording the music is only half of what being a producer is about. Just as important is knowing how to get the best performance out of your artists. Rubin recently produced Damien Rice’s “My Favourite Faded Fantasy,” – the singer-songwriter’s first album in eight years. After such a lengthy break from writing and recording, Rice’s confidence was occasionally in need of a boost:

“I would try to help him finish or just help him get out of his own way. Sometimes I’d say “I don’t think this line is good enough.” But, in this case, he wrote a lot of things that were really good and he just never felt confident enough about them, so it was more about empowering him.”

Perhaps surprisingly, even the great Johnny Cash benefitted from the confidence Rubin had in him. When the producer started working with Cash, the singer was at a low ebb in his career:

“People didn’t care about Cash for a minute. People hadn’t cared for long enough that he was dealing with that reality. It’s like that with so many grown-up artists. They feel this fear of competing with themselves. The thing that he needed to know was that all he needed to do was make great music that reflected who he was at that moment. He didn’t need to compete with himself.”

Cash was at a point in his career, where he felt that all of his best work was behind him, but his work with Rubin sparked a late career renaissance. This was born out of the confidence that Rubin had for the project:

“We’re going to take as long as it takes, like it’s the most important thing in the world, and make the best record of your life. When I said that to Johnny, he looked at me like I was insane. It was just such a foreign concept that he could do something great. I think he was still in a mindset of like, “My chances aren’t good for having a number one single, so why would I write songs if I can’t have a number one single?” It was just changing the philosophy — none of that matters.”

2. It took a while to get Johnny Cash to record ‘Hurt’

The records that Cash made with Rubin are made up of covers, and both the singer and the producer came up with ideas for what those songs could be. Cash’s powerful cover of Nine Inch Nails’ ‘Hurt’ is undoubtedly one of his late-career highlights, but it was a song that he needed convincing to sing:

“There were a lot of songs that he needed to be convincing about. Eventually, he trusted me enough that if I felt strongly about something, he’d do it. I would send him compilations of CDs of songs to listen to, and I remember that on several compilations in a row, “Hurt” was the first song. There’s just something about it. I imagined him saying those words being very powerful.”

3. Sometimes, as a producer, you just need to not get in the way of the band

This is particularly true of Rubin’s work with Slayer:

“With them, it really is about, it’s so specific, what they do, that really so much of the job is just not getting in the way. As long as you don’t interrupt them being Slayer, it’s probably gonna be good. They have a flavor. It’s like the Ramones.”

Specifically, his super-tight recordings allowed the band to play faster and harder than any band had done previously. This is exemplified by his work on their ‘Reign In Blood’ album. In 1986, when the album was released, a lot of heavy metal was drenched in reverb and delay – Rubin got rid of all this, lending real clarity to the recordings – all that was left was the brutal playing of a band at the top of their game.

4. You can’t always predict whether a room will sound good

One of the main things you take away from Dave Grohl’s 2013 film on the Sound City studio in California is that it is, as Butch Vig says: “kinda dumpy”. Despite this, some of the greatest albums in rock history have come out of that studio. Rick Rubin recorded the Tom Petty album, ‘Wildflowers’ there:

“You could do a computer rendering of exactly what the best-sounding recording studio would be, and you could build it, and it still might not sound like anything. I mean, there are weird rooms that’ve been there for a long time, and a lot of people have recorded in them. Sound City is a good example. It was not very well designed, acoustically. But it sounded good!”

5. Rubin doesn’t like his hip-hop too slick

Surprisingly, Rubin isn’t a huge fan of The Chronic – the career-defining album of that other hip-hop heavyweight producer, Dr. Dre:

I never really listened to The Chronic. I guess I never liked smooth? Same with Puff, who really brought R&B into it. I preferred hip-hop when it was nothing like R&B. I love breakbeats and B-boy style drum machines. I never liked the slick stuff.

6. Sucker M.C.’s was a defining moment

You could never accuse Run DMC’s ‘Sucker M.C.’s (Krush Groove 1)’ of being too ‘slick’. Just brutal drum-machines and fierce flow, this track was a turning point in Rubin’s life, and therefore a pivotal moment in hip-hop history.

“Sucker M.C.‘s” was radical. It changed me. It was better than everything else.”

The track was produced by Russell Simmons. Shortly after ‘Sucker M.C.’s’ was released, Rubin and Simmons would form Def Jam – the label that defined hip-hop in the 1980s.

7. Sometimes you can’t compete with the magic of those first demos

There are numerous stories from music history where an original demo has captured some kind of magic that subsequent recordings just can’t capture. Lana Del Rey’s ‘Video Games’ is one recent example. Rubin experienced this on Johnny Cash’s ‘American Recordings’ – and had the nerve to put those demos out as a record.

“American Recordings was demos — it wasn’t even supposed to be an album. We recorded ideas, and then went into a studio with a band to play it again. And it wasn’t as good. When American Recordings came out, it was well-accepted. And Johnny couldn’t believe it. He could not believe it.”

8. Some of his greatest records just couldn’t be made today

The early days of sampling were a completely lawless free-for-all; it was the musical equivalent of the Wild West. Before artists realised how much money they could make from other artists sampling their records there was a real ‘anything goes’ atmosphere. Perhaps something has now been lost, as certain records from that era, by acts such as De La Soul, Public Enemy and the Beastie Boys could never be made today:

“I cleared the use of “Back In Black” with AC/DC and they loved it. But this was in the days where no one knew what sampling was. I remember playing it for Malcolm Young on headphones backstage at an AC/DC concert, and he was like, “Who played guitar on that?” And I was like, “I did.” I mean it’s a combination — there’s samples involved too, but I’m definitely playing. And I programmed the drums.

You couldn’t do it today.”

9. There is some great unreleased Kanye in the vault…

Apparently there are alternate versions of the songs on Yeezus that are as good as the ones that made it on to the album. In fact, Rubin and West have even talked about bringing out an alternative version of the album featuring some of these tracks:

“There are versions just as good as what’s on the album, just different. I know as a fan of the album, I’d like to hear that. Maybe some day, whenever he wants. But it exists! That shit exists.”

10. He doesn’t agree with Kanye on the best album of 2014 though…

Undoubtedly the biggest story to come out of this years Grammys was the fact that Kanye West was pretty unhappy with Beck getting the best album nod ahead of Beyoncé. However, it appears that Kanye’s producer doesn’t share his views:

“I absolutely love Morning Phase. Probably my favorite album of 2014. It’s definitely his best. I like it a thousand times better than Sea Change.”