In a string quartet, the viola and the second violin are commonly referred to as the inner voices, less frequently in the spotlight, yet essential to the core of any ensemble’s sound.
Mary Ruth Ray, as the founding violist of the Lydian String Quartet and as a key member of the ensemble at Emmanuel Music, was one of Boston’s most dependable inner voices.
“She was the glue,’’ said Judith Eissenberg, the Lydian’s second violinist. “She was a leader who leads by connecting people, by building consensus. She had an incredible intelligence and was a very lyrical player.
“It was the perfect combination of talents for an inner voice,’’ Eissenberg said.
Ms. Ray, who joined the faculty at Brandeis University in 1980 and became chairwoman of the music department in 2005, died of cancer Tuesday in Coolidge House in Brookline. She was 56 and had lived in Jamaica Plain.
“Working with Mary Ruth was one the great privileges in my life as a composer,’’ Lee Hyla wrote in an e-mail. “She was deeply musical, she had tremendous soul as a person and a violist, and she was calm and forceful as a chamber musician.’’
Scott Edmiston, director of the university’s Office of the Arts, said in a statement on the school’s website that “Mary Ruth had a profound and lasting impact on the arts at Brandeis, as both a teacher and an artist. Her legacy is one of grace and beauty.’’
Born in Knoxville, Tenn., Ms. Ray began her musical life on the viola, unlike many violists, who begin on the violin and later switch. She was 10 when she met Eissenberg through a common teacher, and they met again at the State University of New York at Purchase, from which Ms. Ray graduated with a bachelor’s degree in music.
In Boston in 1980, the two joined with violinist Wilma Smith and cellist Rhonda Rider to audition for a new resident quartet position being formed at Brandeis. The move was rather bold, given their lack of experience as an ensemble.
“We rehearsed madly for five hours — the first movement of Ravel Quartet, and the Haydn ‘Sunrise’ — and then presented ourselves as a pre-formed quartet,’’ Rider recalled, still sounding slightly incredulous over three decades later. They won the position.
“I remember thinking that Mary Ruth had an incredibly beautiful sound and was just made for chamber music,’’ Rider said.
Over the decades in residence at Brandeis, the Lydian Quartet made itself indispensable to the Boston musical community. The quartet was honored with prizes, most notably the prestigious Naumburg Chamber Music Award in 1984, and earned a reputation for musical intelligence paired with an exploratory spirit. The latter emerged most palpably in its championing of local composers, including Hyla, Yehudi Wyner, and John Harbison.
In 1977, before cofounding the Lydian Quartet, Ms. Ray joined Emmanuel Music and went on to become a core member of that ensemble during the decades when it earned national recognition for its complete cycles of Bach’s Cantatas under the direction of Craig Smith, who died in 2007.
“She’s always embodied the heart and soul and the philosophy of music here,’’ said Ryan Turner, Emmanuel Music’s artistic director. “Her music-making was even poetic at times because of the way that, as a violist, she was engaged in the text and with everybody around her.’’
In 1970, she met fellow violist Leonard Matczynski, who also had a long association with Emmanuel Music. They married in 1978 and had one son. They separated in 2009.
During her decades with the Lydian Quartet, the group built a lengthy discography that encompasses both standard repertory and contemporary works by American composers. In 1987, Smith left the quartet and was replaced by violinist Daniel Stepner. In 2002, Rider departed and was replaced by cellist Joshua Gordon. Ms. Ray also played on several recordings with Emmanuel Music.
A service will be announced for Ms. Ray, who leaves her son, Will Matczynski of St. Paul; a sister, Roberta of Seattle; and a brother, Bill of Nashville.
When reached Thursday, Harbison, who also plays viola, recalled years of watching Ms. Ray closely.
“She exemplified something about the viola temperament: collaborative, alert, not particularly talkative, but aware of what everybody else was playing,’’ the composer said.
“I always told her she was my teacher, because she had a way of playing that broke things down to the most direct sets of issues. She always found a solution that was not histrionic, but was effective and economical.
“I think that, ideally, is what being a violist is all about,’’ he said. “There was just something so right to the core about the way she made music.’’