Few musicians can compare themselves to Bruce Hornsby. Throughout his 18-year career, he has earned respect across the spectrum of music from Top 40, rock and rap to bluegrass, jazz and country. He has appeared on over 60 albums. His music has been sampled by Tupac Shakur. He has worked on soundtracks with Spike Lee. He was a part-time member of The Grateful Dead. A couple of weeks ago he was joined on stage by Bruce Springsteen.

Hornsby and his band recently set off on a monthlong tour, which brings them to the Harbor Center in Portsmouth this Friday, with the accompaniment of a full symphony orchestra. He spoke with Style about his latest album, playing with an orchestra, his most meaningful collaborations, and his ever-evolving sound.

In the past you have played with all types of musicians. What was the best collaboration you were ever a part of?

The most recent, say the last three or four years, the one that comes to mind is the collaboration with Ricky Skaggs on his tribute to Bill Monroe. … Typically, most of the best music is what occurs under the mainstream radar screen. The first song on the record is our collaboration called “Darlin’ Corey,” and we had such a great time doing that that Ricky and I are going to make a bluegrass record together. …

I am really proud of having played on the Bonnie Raitt [song] “I Can’t Make You Love Me.” [“Luck of the Draw”] was such a big record for her, and such a great song. …

Working with Spike Lee has been very special for me. I have written and performed two end-title songs for his movies. So from Ricky Skaggs to Spike Lee, there’s a broad spectrum. Certainly the most long-term collaboration is with my Grateful Dead friends. That’s probably the most substantial, lengthy collaboration, and so in that sense, as far as being most meaningful and most influential, I’d probably have to pick that.

How did you first get involved with the Dead?

They were fans of my first record, and we got a call from them out of the blue to open two shows for them. … Then every year for the next three or four years, they’d always ask us to open two or three shows. Then they asked me to sit in with them after we’d open, then I’d sit in a little more … I’d show up sometimes and just play with them. Then Garcia played on my third record and the relationship just grew from there, from the first opening-act situation to where when [keyboardist Brent Mydland] died, they asked me to replace him. I didn’t want to just be [their] full-time guy, I had too much going on. If they would have caught me in 1984, I would have just done that. But my [solo career] was going pretty well at that time, and so I said, ‘Well I’ll help you out.’ I thought I would do it for a little while, but I ended up doing it for almost two years. And then a bit after that on and off, until really New Year’s Eve of this year was when I quit.

How does the presence of an orchestra change a live show for you and the audience?

Well it changes our approach deeply in the sense that our approach to live playing is really spontaneous and we like to just go from one song to another, or try playing a song we’ve never played before, or stretch a section or take it out. It’s always different. We are always trying to move the music around and do different things. With an orchestra, you can’t do that.

At the same time, there’s another plus: Especially on ballads you get a certain lush, beautiful sound that can’t be really duplicated. I get chills playing certain ballads of mine. It’s hard to give yourself chills when you are playing, and so that’s really an enjoyable situation. We’ll do a few things on our own, hopefully, where we will just sort of let it go a little bit more than we get to with the orchestra. We’ll let it fly a little bit with the orchestra, too.

You have said that your latest album, “Here Come the Noisemakers,” is truly indicative of how you sound. Why did it take you so long to get a live album out?

There are definitely plans to put out more live records. Why’d it take so long? You know, a lot of it has to do with my own performance vocally. It’s the first time I’ve listened to the tapes and went, “Wow, I’m really proud of this. This should come out.”

Who were some of your greatest influences over the years?

As far as influences, certainly the great jazz pianists: Bud Powell, Bill Evans, Keith Jarrett, McCoy Tyner, Chick Corea, Herbie Hancock, Wynton Kelly. In the rock area, Leon Russell has been a big influence, the early Elton John records.

As a songwriter, certainly Bob Dylan is an icon to most songwriters. Getting to play on one of his records and becoming friends with him was very meaningful for me. Robbie Robertson. Elton John and Bernie Taupin, the songwriter. Those are probably the main ones. Randy Newman has been someone I have just loved, and have been influenced by lately. Vocally, Sam Cooke has been an influence for the last several years. Bill Monroe. The Grateful Dead as songwriters.

You have sat in with the String Cheese Incident this winter and Widespread Panic this spring. After playing with the Dead, what do you think of the bands they paved the way for?

I think that they need to go back and listen to the Dead on a songwriting level, or listen to some other people. I think there’s lots of good playing involved there, but I don’t really hear a deep commitment to songwriting in that crowd.

Who is in your CD player nowadays?

Paul Simon’s last record, speaking of songwriting, and Randy Newman’s box set. Neither of these records were commercial successes. Once again, more examples of the best music flying way the hell under the mainstream screen. I love the last Keith Jarrett Trio record; it’s called “Whisper Not.” The new Chris Whitley record, I played for about 20 seconds on the record