He’s one of the best bluegrass musicians on the planet, equally adept at mandolin and fiddle. He’s credited, alongside fellow members of Newgrass Revival, for expanding the genre into jazzier, more progressive territory. He’s appeared on around 400 albums since the early 1970s, including sessions with Steve Earle, Garth Brooks, Tony Rice, and Johnny Cash, and he’s won three Grammy Awards. So it’s probably not often that Sam Bush feels nervous around another artist, but we guess that’s what writing with the late, great Guy Clark will do to a man.

“I’ve been fortunate in that I’ve had quite a few musical big brothers in my life,” Bush says. “And Guy was one of them, for sure. I first knew him from playing on his records and us being jam-session pals. But when I first sat down to write a song with him, it was very intimidating, because I think of him as one of America’s greatest songwriters ever. And as a co-writer you have to have thick skin, because you have to be willing for your writing partner to look at you and say they don’t like what you came up with. And Guy was never one to mince words if he didn’t like something.”

Bush and Clark ended up writing two songs together in that 2009 collaboration, one of which appears on Bush’s dazzling new Storyman album, his first release in seven years. Called “Carcinoma Blues,” it’s a rumination on the effect that cancer has not only on its victims but on the loved ones tasked with taking care of them. “Carcinoma” is a surprisingly upbeat tune by a man who had cancer twice (Bush) and another (Clark) who would die of lymphoma a few years later.

“It was a positive thought to Guy and me that people going through cancer, it doesn’t have to rule you,” Bush says. “It doesn’t have to control your life: Cancer, you ain’t rulin’ me. In fact, I think that in general, my type of songs usually have a positive message. As an overall outlook, I have a positive view in life.”

He’s got a lot to be positive about on Storyman. Each song was co-written with a collaborator, be it someone in his band or legendary American musical figures like Clark or Emmylou Harris. Freely mixing bluegrass, folk, country, and all manner of instrumental virtuosity as Bush and his band often do, it’s an album that’s strikingly cohesive from start to finish, even though it took four years to make.

“Well, I work on other people’s records a lot,” Bush says with some understatement. “So between that and going on the road, I just get busy, and that’s one reason it took four years. But I also wanted to wait until I felt like I had something to say and that these songs could stand. I wanted to give it time and attention. I probably had about 19 or 20 songs with different friends to choose from, and I know we’re in a day and age where people like to buy one song at a time. But for me it was still important to have a collection of songs that went together. And although there are different styles within the record, it’s cohesive and these songs fit together in a package.”

Bush had actually planned to make his previous album, 2009’s Circles Around Me, an all-collaborative effort, but in the end he mixed some co-writes in with traditional bluegrass tunes. “After I did that one, I knew that I wanted to do an all-co-writing album,” he says. “It’s only in the last 15 years that I’ve been enjoying the method of co-writing. And within that we still have some instrumentals, and there’s one called ‘It’s Not What You Think.’ That’s the first time the five of us in the Sam Bush Band sat down to write together. And that was a wonderful experience. Every time I left the room and came back, the tune was better. So I hope we get to repeat that with the five of us.”

Another surprise on Storyman is the warmth and strength of Bush’s singing voice. He’s always been a vocalist to varying degrees on his albums, but his voice has been more and more of a focal point as his career has progressed. “Probably part of it is confidence,” he says. “When I was a kid I didn’t pay as much attention to singing. I only listened to the instruments. But I’ve had two or three great vocal coaches in my life. Garth Fundis, the Newgrass Revival producer, was good for me and helped me learn different ways to sing. Then for 15 years with [Newgrass Revival singer/bassist] John Cowan, I tried to sing as loud as I could to keep up with him. Then when I spent five years with Emmylou Harris’ band, she taught me more about softening up and increasing my range a little bit. I’ll read reviews where they say, ‘His vocals are an acquired taste.’ Well, I’ve been reading that about Bob Dylan for 50 years, so I’m OK with it.”