As a young musician living in an unheated New York City apartment, Robert DiDomenica wore a hat and gloves as he worked so he could keep composing, never skipping a day.
A gifted flutist much in demand in the 1950s and '60s, he often traveled with orchestras and ensembles, holding his inkwell on bus rides so it wouldn't spill in his luggage and renting a piano to compose in his hotel room during longer stays.
"He wrote every single day of his life," said his wife, Ellen Bender, also a flutist and composer. "He would often say that writing music was life and death, no compromising."
As patient as he was persistent, Mr. DiDomenica waited years or decades for some compositions to be performed, uniformly to acclaim. His First Piano Concerto, composed in 1963, premiered in Boston's St. Cecilia Church in 1995.
Mr. DiDomenica, who spent 23 years at New England Conservatory, where he was a revered teacher and served as dean, died of pneumonia May 20 in Avery Manor, a Needham nursing home. He was 86 and had lived in Needham for many years.
"I could write a whole book about him," said composer and conductor Gunther Schuller, who was best friends with Mr. DiDomenica since the 1940s. "One of the very good things I did was to bring him to the New England Conservatory when I became president. He was a very fine flutist, but he also was a remarkable composer, so I got him to the conservatory as a composer. He was a very, very beloved teacher."
Mr. DiDomenica also was a much respected composer. Along with Schuller, those who championed his work included Sarah Caldwell, who premiered Mr. DiDomenica's 1972 opera "The Balcony" in 1990 with the Opera Company of Boston and brought it to the Bolshoi Theatre in Moscow. In 2002, James Levine opened a Munich Philharmonic program with Mr. DiDomenica's "Symphony 1961," helping secure the composer's international reputation.
"I have always had recognition from people I care about, but the list was not long," Mr. DiDomenica told the Globe in 2002. "I never complained because I was so lucky to have what I had. But it was a fantastic experience to have someone with Levine's position in the musical world hear your piece out of the blue and like it and tell you that it is good. I just wanted to hug him."
Mr. DiDomenica also composed for chamber ensembles, voice, and for piano, notably pieces for his first wife, the former Leona Knopf, whom he married in 1951. A pianist and teacher treasured by Boston's music community, she died of cancer in 1998.
Focusing mainly on opera in his later years, Mr. DiDomenica fashioned his own libretto for each piece.
"He was always writing me poetry," Ellen Bender recalled, "and I set many of them to music as song cycles."
Reviewing a recording of Mr. DiDomenica's orchestral works in 1999, Globe critic Richard Dyer wrote that all of his music "is marked by precision of ear, clarity of musical logic, discipline and ingenuity, and perpetual surprise. This is a composer who writes nothing for effect, who stops when he's done, but whose music leaves an indelible impression because of its seriousness, humor, inevitability, and utter integrity."
Uncompromising even when a score was finished, Mr. DiDomenica told the Globe in 1975 that as a younger man he wrote a flute piece on commission, "but I gave half of the money back because I hadn't written what I wanted."
Mr. DiDomenica "believed that inspiration was a product of hard work," his wife said. Meticulous and exacting, he played passages over and over while composing, patiently testing different tempos and dynamics.
"Some artists say they wait for inspiration. That's not Bob's philosophy," she said. "He said you have to work every day. Every day helps to further what you're doing. Even if nothing happens, if you're still writing, you're discarding and accepting, and the next day will be better. You work every day and hope something will happen, and it will, if not that day, then the next day."
Growing up in New York City, Mr. DiDomenica was an only child whose father was a pattern maker for the garment industry and whose mother painted. His father also was a tenor in church choirs and loved opera.
He graduated from New York University and as a flutist ranged widely in his performances, from Broadway shows to the New York City Opera, the New York Philharmonic, the Bach Aria Group, and the Modern Jazz Quartet.
"He had one of the most beautiful flute tones that I've ever heard," said Schuller, who drew on his friend's talents when he needed a flutist for a chamber performance.
Mr. DiDomenica, Schuller said, "played everything from a composer's point of view. In other words, he was one of those musicians who understood how the piece was composed. When you put that into your playing, you're not just playing the notes. He did this with any composer's work, whether we were playing Stravinsky or some yet unknown composer. I always knew that with him I could rely entirely on his insight into the music."
In 1969, Mr. DiDomenica and his family moved to the Boston area so he could teach at New England Conservatory.
"He's one of these teachers that students never, never forget," Schuller said.
Among his many students was flutist and conductor Paul Dunkel, who was a boy in New York when Mr. DiDomenica became his first flute teacher.
"He brought a love to the instrument and to music that my previous teachers on the piano couldn't," Dunkel said. "In retrospect, he had the calmness of a Buddhist combined with this great, great joy that made every moment a tremendous amount of fun. Even when I was a youngster, he gave me a great sense of purpose."
The family will hold a private service for Mr. DiDomenica, who in addition to his wife, Ellen, leaves three sons from his first marriage, David of Needham, Peter of Millbury, and Claude of Norwood; and four grandchildren.
Mr. DiDomenica's works are archived at Harvard University and the Library of Congress, and when preparing to send his papers to the latter, "he didn't want them to have to do anything," his wife said. "He put everything in folders. He made lists. He put things in order."
He was just as attentive to people, from students to caregivers at the nursing home.
"He appreciated everyone. He also appreciated life," his wife said. "He wanted to live as long as he could. He always said he wanted to live for me. He had a tremendous heart, and no one else could have been loved more than he loved me."
Bryan Marquard can be reached at bmarquard @globe.com.