When it comes to acoustic guitar players, few have had the impact of Scottish singer and songwriter Bert Jansch.

A key figure in the British folk revival of the 1960s, Jansch started out in small clubs, redefining the way traditional folk could be played, then mixed a variety of genres as part of the celebrated acoustic group, Pentangle, which still performs in Europe today.

It’s his lovely solo work that is the most affecting to these ears, ever since I heard an early version of the hauntingly beautiful “Needle of Death.” His songs are earthy, with unusual rhythms and unconventional time signatures, beautifully played. And they influenced a slew of better known artists, such as Jimmy Page (who famously ripped off Jansch’s arrangement of “Blackwaterside” for Led Zeppelin), Paul Simon, Neil Young, Donovan and Nick Drake. More recent acolytes include Beth Orton and Johnny Marr of the Smiths.

Jansch has experienced a career revival in recent years. In 2005, the acclaimed indie film “The Squid and The Whale” prominently featured his haunting song, “Courting Blues,” leading to a deal with indie label, Drag City, which released a new album from Jansch (“Black Swan”) and reissued three of his classic ’70s records. Last year, longtime fan Neil Young asked him to go on tour as support so that larger audiences could discover his music.

“As much of a great guitar player as Jimi [Hendrix] was, Bert Jansch is the same thing for acoustic guitar … and my favorite,” Young was quoted.

But sadly, Jansch’s resurgence has been marred by health problems. While he has always continued recording and releasing albums, a long bout with alcoholism in the ’80s nearly killed him, and he was recently diagnosed with throat cancer — for which he is receiving treatment between tours. He’s had to cancel tours before because of health scares that had him at death’s door.

Talking to him from his home in London, where cell phone-distorted music can be heard playing in the background, Jansch comes across as friendly but guarded. He doesn’t offer much elaboration on his music or motivations. He seems more excited when talking about others’ work than his own.

Style: How have you dealt emotionally with the rollercoaster ride of hospitals and cancer treatments and then suddenly playing to the largest audiences of your career?

Bert Jansch: I must say it was a bit strange at first. But I’m handing it all right, it’s fine. Yeah, it’s good. The hospital thing is just an ongoing thing that will be on for the rest of my life, I suppose. But audience-wise it was great. It was a fantastic way to take my mind off it.

How has Neil Young’s audience taken to your music?

It got better and better as the tour went on. Starting at the front they are generally a bit noisy. But as the set went on and it filled up with people, it was like, “they’re really listening.” It was great.

Does the sound in these larger halls present any difficulties for your intricate style of playing?

No, because the sound is fantastic. Playing in big halls like that can be a bit daunting but the sound systems really are amazing nowadays. I generally don’t like to play really big gigs because you don’t get any real intimacy at all with people running about.

I’m sure it gets harder as you age to manage the physically demanding part of playing those songs.

Well, I think I’ve mellowed out quite a bit. I’m not in the game of playing the fastest, longest, and more complicated [laughs]. I’ve tried to simplify as much as possible. It does tend to sound better if it’s simpler.

The unusual rhythms and unconventional time signatures– did those come more from the way you write songs — writing to accompany the lyrics for example — or something else?

Well, I think it’s a combination of things: Listening to folk music, because folk musicians don’t have a sense of keeping up the rhythm in between the lines, if you know what I mean. So they’ll literally come in [in] the middle of a bar or whatever. Once you get used to that, it’s quite nice.

Also working with Pentangle, the whole band was well into weird time signatures. I don’t know. I don’t write that way nowadays. There’s still a little throwback, I suppose, from all the idiosyncrasies.

How do you write nowadays?

I have my own studio here which I use for writing and demoing stuff. But usually I still write just for guitar, doesn’t matter where I am.

Some of my favorites of yours are the sadly beautiful ones (“Needle of Death” being a classic example)–but I’ve read several famous musicians use words like “violent” and “angry” to describe your early work. Do you understand that?

Oh yeah. Well I don’t know about violent. But angry occasionally, yeah, but those are just emotions. I do tend to show emotions through the guitar rather than any other way.

I also heard you were a big fan of Charles Mingus. Was there any specific American artist that had the most effect on you?

An American? Oh, I don’t know. I listen to such a varied cross-section . . . [John Fahey], yeah he was interesting, he was good. But I’m much more into stuff like Doc Watson. I really do love folk music of all kinds. When I first started, along with my love for the guitar, I went to a lot of folk clubs and consequently, I heard a lot of traditional stuff. At the time I didn’t realize I was being that influenced by it. After Davey Graham did albums like “Folk Blues and Beyond” and the record he did with Shirley Collins. Those had a great influence on me. And I’ve been interested in folk music ever since.

It seemed a lot of younger fans were turned onto your music from “The Squid and the Whale” soundtrack in 2005 — did you notice a bump in your American audience?

Oh yeah. And since the reissues on Drag City [“L.A. Turnaround” (1974); “Santa Barbara Honeymoon” (1975); and “A Rare Conundrum” (1977)], it’s been great.

Did you and Neil ever play together on this tour?

No, because his set is defined. Also, most of his set is electric — except for the front end is acoustic. Starts off acoustic for four songs and it then goes electric, and it really is loud. I wouldn’t want to be sitting in the front.

Are there any of his songs you particularly like or would want to play with him?

We did “Ambulance Blues” at the Bridge School Benefit once. But I didn’t actually know it at the time, which is a bit of a shame. I had about five minutes to learn it. But if we do get around to it, I wouldn’t mind redoing that one. Because I’ve been playing it quite a bit actually. … No, I don’t do a radically different version. Pretty much in line with his.

What are you working on now?

I’ve been working on a Pentangle live album from shows we did in 2008. We’ve got all the tapes from that tour and I’ve been compiling it – it’s pretty good stuff. We’re doing some more shows over here, but haven’t gotten as far as going abroad yet. Working with Pentangle I’ve been playing banjo quite a bit, and it sounds totally different than it used to.

Do you think that Pentangle has accomplished all it is capable of?

No, no, I don’t think so — but there’s been a large gap between those days and now. So this [live] one is mostly old [material]. … I think if it goes to plan, it should be out in September. I can’t say which label yet.

When you were going through your drinking days as a performer with them, did you ever feel guilty like you weren’t respecting the music — or were you always pretty functional?

Oh I don’t know — that’s for the listener to decide that one.

I don’t guess there’s any chance you’ll do anything with your old friend, Clive Palmer.

Well no, it’s all a question of location really. He lives between Normandy and Cornwall, and unless you’re in that vicinity, then. … I did not hear his last solo record. Clive’s Original Band: C.O.B., that’s the last time I was listening to him.

Anything you’d like to get out there — maybe tell people to shut up at the show?

[Laughs] No, no. Just enjoy the show. Neil’s show is absolutely amazing to watch. During the last part of the tour I sat right through all of the shows from backstage, mind you.

And you’ll be playing mostly new material from “Black Swan”? Any chance we’ll hear classics from “LA Turnaround’ or your first album?

I may play a few old ones. But as you know well with the likes of Neil and myself, you don’t necessarily get what you want.

Bert Jansch is appearing as the opening act for Neil Young at the Landmark Theater on April 17. Tickets are still available through Ticketmaster and at the Landmark Theater box office. They range from $57 to $202.