Cover art for Rockabye Baby’s album "Lullaby Renditions of Beyonce," which was released in February. (Rockabye Baby)

Pro tip for aspiring PR executives: If you’re ever announcing a Beyoncé-themed baby product, try to do so just days before she Instagrams her pregnancy.

Such was the most recent stroke of good news in the potent, enduring tale of the Rockabye Baby series, which for 11 years and 78 albums has tried to alleviate one of the worst parts of being a parent — the music — with lullabied instrumental covers of songs from, you know, real bands. The Beyoncé version is the latest in a list that includes Prince, the Beatles, Springsteen, the Pixies, David Bowie, Eminem, the Cure, Guns N’ Roses, Rush, Kanye West, Radiohead, Adele, Cyndi Lauper, Tool and Iron Maiden. (If you think you had a weird day at work, imagine trying to coax “The Number of the Beast” out of a harp and glockenspiel.)

(Rockabye Baby)

(Rockabye Baby)

In its field, the Rockabye Baby series has carved out a “Weird Al”-esque dominance: 1.6 million units sold, 1.8 million single-track downloads and 130 million streams, although, to be fair, some of those might be from parents who have totally nodded off. Rockabye’s wares — branded by a decade-old design template and teddy bear mascot — are prominent in boutiques and baby shops nationwide. Steven Tyler and Joe Elliott wrote liner notes for their bands’ versions; Elton John and Metallica’s Kirk Hammett have gushed to the media. And the company’s approach is a sweet marketing dream: Infants drift off to calming, twinkly soothe music, parents get to preserve some version of their pre-Honda Odyssey selves, Pitchfork gets to post the planet’s most huggable LCD Soundsystem cover, and everyone goes to sleep happy.

“The obvious audience is the parent-slash-music-fan who has a sense of irony,” says Lisa Roth, executive producer of the series. “The musical palette is for the baby, but the packaging and homage to the artist is for the adults.”

The Beyoncé installment, released Feb. 24 and produced and performed by Andrew Bissell, includes definitive marimba-and-glockenspiel versions of “Hold Up,” “Sorry,” “Drunk in Love” and other songs that would get pretty much anyone fired from a day care. That said, it’s fairly shocking how well the melody of “Single Ladies” translates to bells and a xylophone.

Roth says that’s the sweet spot — the intersection between irony and rebellion, pre-baby rage with post-baby softness, the desire to raise thoughtful, fulfilled children with the reluctance to commit oneself entirely to bottle warmers and baggies of Goldfish.

“When you’re a parent, there’s a part of you that gets put on the back burner,” she says. “I like to think we’re a little bridge between the person you were pre-baby and the person you think you have to become post-baby.”

The Beyoncé lullaby record wasn’t pegged to the queen’s pregnancy — Roth found out about it on Instagram, just like all of us. And Beyoncé would have gotten a lot of attention anyway. “It was just super-with-a-cherry-on-top lucky,” Roth says. Pitchfork and Okayplayer blogged positively about the fetus-appropriate version of “Single Ladies”; NPR premiered “Hold Up” online.

“So much of the kid-friendly music out there is super commercial or obnoxiously saccharine and painfully grating,” says Robin Hilton of NPR’s “All Songs Considered.” “But these tinkling little instrumentals are oddly comforting. A large part of the appeal is the simple novelty of it all. But these are also really deftly arranged. They stand on their own. They also tap into the kinds of bands parents today would have listened to growing up, so there’s a real nostalgia factor.”

(Rockabye Baby)

There’s also the factor of being spectacularly marketed. The series is part of the CMH Label Group, the 45-year-old bluegrass-and-roots indie that houses the Vitamin String Quartet and the Pickin’ On series, which similarly reboot rock/pop songs into orchestral and bluegrass numbers. “I always call it an idea company, not a record label,” Roth says. “We produce concept brands.”

Roth — the sister of David Lee — didn’t grow up an especially lively rock fan, skewing more to the ’60s Motown and Stax sounds. But when she launched Rockabye Baby in 2006, she knew the metal angle would draw eyeballs. “ ‘Lullaby Renditions of Nine Inch Nails’ is way better than ‘Lullaby Renditions of James Taylor,’ ” she says, laughing.

CMH initially took the traditional route for Rockabye Baby, planting product in traditional music and big-box stores. But sales came in well below expectations, and attention proved hard to come by, particularly in a decaying record industry that was commanding less and less real estate in a Walmart. On the advice of a consultant named Francie Kaplan, who had worked with Disney and Mattel, Roth tossed aside 30 years of marketing history, moved Rockabye Baby to upscale boutiques and specialty shops, and she maintained its premium pricing, aiming the albums squarely at the quietly seething demographic of parents unprepared for a full plunge into Radio Disney. Kaplan “helped with the branding, the look, the sound, everything,” Roth says. “Slowly but surely it came together in that first couple of years.”

The branding was a coup. Almost all Rockabye Baby releases sport the same design, typography and color palette. They also are lousy with puns — the Beyoncé edition depicts the mascot-teddy in a black “Formation” hat drawn low. This is a standing gag and part of Rockabye Baby’s branding — the Bob Marley edition is a parody of the “Burnin’ ” cover, David Bowie’s bears an “Aladdin Sane” lightning bolt and Pearl Jam’s is the “Ten”-era “Alive” guy redrawn in cuddly bear form. (Three guesses at to what the cover looks like for “Lullaby Renditions of Songs From ‘Hamilton,’ ” released March 31.)

Aside from Bissell, who also worked on Blur, Bon Jovi and the Police, the producers charged with finding the infant-appropriate melodies lurking beneath Kanye West’s “Gold Digger” and AC/DC’s “Rock and Roll Ain’t Noise Pollution” include Steven Boone and Leo Flynn, who have been with the series since its conception. “In the transformation process, if something strikes me as funny, I know we’re getting somewhere,” Flynn says.

(Rockabye Baby)

(Rockabye Baby)

An MTV baby who studied at the Berklee College of Music in Boston, Flynn got into writing, arranging and production as part of a study track that prized diversity — “working within any kind of parameters a gig could throw at you,” he says. As such, he was one of a few people on Earth for whom a job turning Queen into baby music made perfect sense.

“To take this piece of heavy metal music and turn it into this diametric opposite while making sure it’s perfectly identifiable — I couldn’t resist the challenge. It’s what I trained for,” he says.

It takes about a year to get what Roth calls the “perfect clunk and tinkle” — the Goldilocks zone between rock rebellion and night-night calm. “We don’t take making lullabies lightly around here,” she says.

The process begins with dismantling the original track in search of its intention. “Then it’s: ‘How do I get that intention across in little short, plucky notes?’ It’s a lot of musical information to crunch,” says Flynn, who adds that his initial attempts on tracks by Queen and Kanye West came off as too aggressive and too noisy, with too many things hitting at once. So the process became more about taking away. “You’re trying to tone down the number of things going on, while trying to preserve the identifying parts,” he says. Final versions go back to Roth and production partner James Curtis for eight to 12 rounds of revisions.

Flynn’s hardest project was — wait for it — Van Halen, which Roth waited awhile before attempting. (“You don’t mix family and business,” she says, laughing, “at least not this family.”) The problem for Flynn was the best part of Van Halen — two searing focal points that demand your attention. “The guitar is very much the feature,” he says, “but the vocals are the protagonist of the story, so your ear naturally goes to those. I really ended up in awe of how that band works.” (For the record, Roth says her brother loved the final version, which is available on the official Van Halen Web store.)

Van Halen was one episode in Flynn’s constant challenge — crafting tracks that appeal to parents and the valuable 0-2 demographic. “You’re putting together a rock or a hip-hop track, as well as this beautiful little piece of music, and you hope you’re pulling off both,” he says.

If the music gets too heavy — a constant concern when dealing with Iron Maiden — they’ll throw in an ambient sound effect — a blowing breeze, a chirping frog. “Even though we’re in the bowels of a heavy, dark song,” Flynn says, “it reminds us that we’re in this whimsical lullaby world.” He ­applied this treatment to a just-finished Doors edition; next up is the Beastie Boys.

Which leads to an obvious question: Are there bands that can’t be lullabied?

“Never,” Roth says. “You would think a band like Black Sabbath that’s all minor chords, or somebody like Kanye, who sometimes raps with the melody missing, would be a challenge, and they were. But that’s the art of it — if we may say so ourselves, there is an art form here.”

Roth pauses for a moment. “Well, maybe a spoken-word William Shatner recording. That would be hard to translate.” She laughs. Maybe, but the cover would be amazing.