A master songwriter celebrates his 50th, with a song for each year

Stephin Merritt rehearsing at MASS MoCa prior to this weekend’s performances there.Steven G. Smith for The Boston Globe

NORTH ADAMS — Stephin Merritt is getting personal.

The prolific musician writes songs by the bunches, but when offstage, he displays a deep comfort with lingering silences. His songs are populated by characters through whom his very dry humor emerges, but throughout a deep body of work including concept albums by pop group the Magnetic Fields and songs written for stage and screen, glimpses of his own life have been hard to positively identify. He can be like a comedian who not only resists letting you in on the joke but neglects even to acknowledge that he’s being funny.

But for his latest project, Merritt is removing many of those artful barriers. Inspired by his 50th birthday last year, “50 Song Memoir” is an autobiography in song — one song for each year of his life. An album by that name will be released in spring 2017. And a concert presentation of the material, structured as a two-night event, has its world premiere Friday and Saturday at Mass MoCA. From there the show will travel to Brooklyn Academy of Music’s Next Wave Festival, followed by a springtime tour of two-night stands, with half of the album performed each evening.

“I tend not to believe that other people’s music is autobiographical even when they say it is, like with Joni Mitchell or James Taylor,” Merritt said. “I think it’s probably, maybe, suggested by things that they’ve done or elements of their personal lives. But in this case, almost everything on the album is literally true. A few things are only figuratively true. But I think pretty much everything is true on some level.”

Merritt was on a rehearsal break in the green room of Mass MoCA’s Hunter Center, where he and his cohort are spending two weeks in residence as they work on the material. He wore a dark leather cap, a houndstooth blazer, and baggy trousers; as is his custom, he was wearing shades of brown, exclusively. In conversation he considers each question thoughtfully, often punctuating his responses with extended ellipses. Only occasionally, an impish grin flashed across his face.

“My friends and relatives will hear the album, so I better not misrepresent them,” Merritt said. “My mother will be in the audience listening to me singing about her. There’s a lot more vulnerability than I’m used to.”

“50 Song Memoir” is credited to the Magnetic Fields, an expanded version of which backs him for the concert incarnation. He’s been recording with that ensemble since 1990 and occasionally with offshoot groups Future Bible Heroes, the Gothic Archies, and the 6ths. But his creativity finds other outlets far outside the standard pop-band format. He’s adapted Neil Gaiman’s “Coraline” for the stage and collaborated with director Chen Shi-Zheng on a trio of musicals, and also written music for films, commercials, and to accompany audiobooks by Lemony Snicket (also known as Daniel Handler, a sometime musical collaborator). In 2014 he published a collection of poems celebrating the 101 two-letter words found in the official Scrabble dictionary.

Merritt sat on the Hunter Center stage earlier in the day, his chair surrounded by colorful detritus meant to evoke a mixture of living room and nursery, including a wooden pig, a toy robot, and several tin dollhouses from his collection. He was separated from the band by a three-sided sound barrier, made necessary by the painful hyperacusis he experiences in one ear but doubling as a set piece evoking a life-size dollhouse. A projection screen would soon be added to the top of the structure.

On this afternoon, the ensemble — which includes Sam Davol, Pinky Weitzman, Quince Marcum, Chris Ewen, Shirley Simms, and Anthony Kaczynski — was moving quickly through the second set of songs, working out the arrangements and onstage mix. Merritt wants to be able to hear only the bare minimum he’ll need to sing the songs properly.

“If everyone doesn’t sing on the first line I’m going to be terrified because I’ll be singing alone, in bad falsetto,” he warned after one number.

Some of the music is lush and stately, with little evidence of the synthesizers and electronic beats present on most of the Magnetic Fields’ albums. A song called “Be True to Your Bar” feels slow and methodical even before Merritt asks for the band to play slower. “It needs to be national-anthem-slow. It in fact is a national anthem for alcoholics,” he explained. The words offer a peek into Merritt’s process: “Sitting in bars and cafes/Writing songs about songs and plays within plays.”

There are electronic textures on other songs, and some seem to form little suites as the soundscape evolves — an accidental effect, Merritt said.

Theater director José Zayas, who is also Merritt’s partner, kept quiet watch from the back of the room. Zayas is working on the staging elements and helping Merritt with the pre-written banter the singer will use to introduce his songs, giving his ensemble time to switch among the 50 or so different instruments onstage.

“A lot of it is about shaping it to remain his particular persona and character, which can be very dry and distant,” Zayas said of his role, “but also how to open it up and allow a level of vulnerability, which is unusual for him, to peek out. . . . This is him communicating with the audience in a different way for the first time.”

The shape of that persona, Merritt said, is largely out of his control. He’s opening up more personally with “50 Song Memoir,” but he believes the effort will still be filtered through the existing expectations of his audience.

“Even though I’m saying strictly true things, the audience will perceive them within the mirror of my persona — much of which was not created by me. And I can’t control that part,” he said. But he also insisted he’s “exactly the same person” whether onstage or off, “for better or worse.”

Band members started to drift into the green room as a meal break neared its conclusion. The last two hours of rehearsal were due to be spent filming sequences to be projected onstage during the show. For that the musicians would don animal costumes.

Even Merritt?

“I’m the squirrel,” he said, and flashed one of those infrequent grins. For just a moment, he was inviting anyone to be in on the joke.

The Magnetic Fields: 50 Song Memoir

At Mass MoCA in North Adams, Nov. 18 and 19 at 8 p.m. Tickets: $35-$55 for one show or $60-$100 for both. [phone], www.massmoca.org