The folk tradition runs thick with Ruth Ungar Merenda. Her father Jay Ungar and stepmother Molly Mason have been playing music together since the late 1970s and are highly respected acoustic string musicians. Her mother Lyn Hardy is another accomplished singer-songwriter and guitarist in the folk and country vein.

Ruth has carried on the family tradition with her husband and long-time musical partner Michael Merenda, a Durham native. The couple, known jointly as Mike and Ruthy, just released their second album as a duo, “Waltz of the Chickadee,” which they’ll introduce to the Seacoast with a show on Friday, June 5.

Many of Ruth’s family members perform on “Waltz.” Jay Ungar plays fiddle and mandolin on certain tunes and Molly Mason plays bass on several tracks. Lyn Hardy adds backup vocals on a couple of songs. Mike and Ruth both sing and play guitar, while Ruth adds fiddle and Mike also plays banjo. A number of close friends pitch in other instruments, like drums, violin and cello.

The intimacy of the musicians comes across throughout the album. Most of the songs are warm and soft, with banjo strings plucking and upright bass thumping, evoking the feel of a household gathering of close friends and family. Generally more laidback and less peppy than Mike and Ruth’s former band The Mammals, the music feels, as Ruth puts it, “more like sitting on the front porch having a beer than down at the barn dance.”

That should make for appropriate listening at The Red Door in Portsmouth, where Mike and Ruthy will play a CD release show on Friday, June 5. They’re no strangers to the venue, having performed in the Monday night Hush Hush Sweet Harlot music series more than once. Many other Seacoast fans will remember the pair from their numerous area shows with The Mammals.

But Mike and Ruth’s musical affiliation actually began long before The Mammals became national staples of the folk and bluegrass scene. In fact, they played music together the very first time they met in 1998, at the home of a mutual friend in New York City. Ruth, a native of Woodstock, N.Y., moved to the Big Apple after graduating from Bard College, where she studied theater. “Some of my friends were introducing me to their new roommate, and that was Mike,” she said.

Despite her musical upbringing and family background, Ruth had mostly given up music at that point in her life. But when Mike picked up a guitar and started to play, she was compelled to harmonize. “It inspired me to get my dusty fiddle out of the closet with its rusty strings and see if I could play a little bit,” she said.

Just as Mike helped reawaken Ruth’s musical passion, her old-timey folk and country proclivities rubbed off on him. Growing up in Durham and attending Oyster River High School, Mike had played in a number of rock and ska bands and was tuned in to the indie scene coming out of UNH. He graduated from Bowdoin College in Maine with a degree in creative writing before moving to New York and meeting Ruth, who helped carry him in a new musical direction and got him hooked on banjo.

“We definitely learned from each other,” Ruth said.

Within a year, the pair had gathered some friends and formed a band called Rhinegold (“Named after the beer, I will admit,” Ruth said). The group was active for about a year before Mike and Ruth fled the high rents of New York and settled in western Massachusetts. There they met musician Tao Rodriguez-Seeger, grandson of legendary folk icon Pete Seeger. This trio would form the foundation of The Mammals.

“That band really just took off,” said Ruth, who still seems amazed at The Mammals’ early momentum. The band also recruited Mike’s brother, fellow Oyster River grad Chris Merenda, on drums, deepening the already rich family ties.
The Mammals would release six live and studio recordings and repeatedly tour the nation with shows as far and wide as Florida and California (not to mention at least two shows at the Mill Pond Center in Durham). They even traveled to Denmark and Australia.

“We had a lot of fun in that band,” Ruth said. “We had to like forcibly decide to not do Mammals gigs in 2007 when I got pregnant and we needed to slow down a little.”

It was toward the end of The Mammals’ tenure, in the fall of 2006, that Mike and Ruth got married. Instead of traveling to an exotic island for a honeymoon, the newlyweds stayed home and recorded their debut Mike and Ruthy album, 2008’s “The Honeymoon Agenda.”

“It was sort of a way of redirecting our honeymoon funds,” Ruth said, noting that their friend José Ayerve produced the album for free as a wedding gift.

Mike and Ruth took advantage of the disc to record some of their all-time favorite folk songs by artists like Etta James, Bob Dylan and Tom Waits. “Waltz of the Chickadee,” however, is composed mostly of original tunes by the two songwriters, plus a couple of covers by folks like Woody Guthrie and Dave Van Ronk. 

Whereas The Mammals’ breed of bluegrass was upbeat and dancy, evoking a festive sonic atmosphere, Mike and Ruthy’s new disc is mellower and rootsier, with a personal touch augmented by the family participation.

“I think the songs are really strong because they’re all really close to the heart,” Ruth said. “The themes tend to be birth and death, things like that, that seem really intense, but the whole record is gentle.”

Now living in upstate New York with their 1-year-old son William Puck, Mike and Ruth have managed to find songwriting time between their household chores and parenting duties. Each of them wrote a song for Will on the new album, and the baby has provided renewed inspiration for their music. Ruth said parenthood has caused the couple to “look at the world through slightly more grownup eyes, but also through little kid eyes,” and that perspective has permeated their songwriting.

Though they’re still touring in support of “Waltz of the Chickadee,” Mike and Ruthy have also written enough material for a third album, tentatively called “Rise,” which they hope to complete by the end of the year. Ruth said that disc will be more of a dance-happy, full-band effort, reminiscent of their work with The Mammals.

Although The Mammals are “hibernating,” as their Web site explains, Mike and Ruth remain active in other projects, as well. Ruth is a member of the female vocal trio Sometymes Why, and both of them still occasionally play with Tao Rodriguez-Seeger. They even performed with Tao and Pete Seeger at the New Orleans Jazz & Heritage Festival in April, and again at Seeger’s 90th birthday bash in Madison Square Garden in May (the evening’s lineup also included Bruce Springsteen, Joan Baez, Dave Matthews, John Mellencamp and many others).

But Mike and Ruthy are currently focused on the family front, and part of that family is on the Seacoast. Mike’s parents still live in Durham, and Ruth said she looks forward to performing again in the snug confines of The Red Door. But she warns fans not to be late—they’ll only be onstage from 8 to 9 p.m.

The Red Door is at 107 State St., Portsmouth, 603-373-6827. Visit www.mikeandruthy.com.