Professor Charles: Rosen Gifted pianist who became as well known for his writing

His National Humanities citation noted his 'ability to join artistry to the history of ideas'

Charles Rosen was a pianist who became known as much for his insightful writing and talking about music as for making it. His encyclopedic knowledge made itself felt on and off the stage for more than five decades. His concert-hall repertory extended from Mozart to Debussy to Elliott Carter, making it so hard to pin him down that his recording label, CBS, eventually gave up on his contract.

His versatility served him well as a scholar. Having taken up writing in a kind of self-defence – "to begin with I wrote just to keep nonsense off my record sleeves," he said – he won a National Book Award for his first major book, The Classical Style (1972).

It was a thoughtful, erudite and soundly argued study of the music of the three principal composers of the Classical period, Haydn, Mozart and Beethoven. It remains for many the definitive book on the music of that era. Filled with examples of notated music, the book was at times a demanding read for a lay audience.

The Classical Style launched a writing career that extended through several other volumes. Rosen also became a prodigious contributor to the New York Review of Books, writing about classical composers as well as other subjects including the philosopher Isaiah Berlin, the cookery book writer Elizabeth David, Parisian art exhibitions and the Restoration-era playwright and poet, William Congreve.

Rosen said writing was his hobby. "At the piano, if you practise 10 hours a day, then you have no time to write," he said. "I really can't practise more than about four to five. I can play the piano for eight to 10 hours a day, but I can't practise for that long. So I have to do something with my time."

Rosen attended the Juilliard School of Music in Manhattan and then studied with the pianist Moriz Rosenthal, who had been a pupil of Franz Liszt. The connection to Liszt put Rosen in a direct line with the grand romantic tradition that was later to become the subject of one of his books.

Rosenthal was no slouch at the kind of one-line put-down that Rosen was to incorporate into his writings. He also connected his young student with the musical and intellectual life of New York. When Rosen matriculated at Princeton, he recalled, he already knew the whole music department and what it might have to teach him. Instead, he majored in French literature, earning a doctorate from Princeton in 1951. He won a Fulbright scholarship to study 15th-century musical manuscripts in Paris.

His piano career continued with high-profile performances at Town Hall in New York and the release of his first recordings. Of his rendition of Brahms' Variations on a Theme of Paganini, Time wrote in 1952 that the 25-year-old pianist "swept along like a fresh breeze in a musty corridor, slamming doors on heavy-handed traditions and uncovering the fine old structure. Listeners heard more details than they believed possible, played in tones of pastel shading."

A year earlier, Rosen had created a minor sensation with the first complete recording of Debussy's Etudes, and his record label thought of him as a French specialist. The connection to France sustained him throughout his life, and he maintained residences in Paris and New York. But he defied categorisation, recording Bach, Beethoven and Pierre Boulez, who along with Elliott Carter, a friend who died last month at 103, remained one of his artistic touchstones.

Because of his allegiance to Boulez and Carter, Rosen had a reputation for playing contemporary music, but his taste was for the kind of smart modernism that these composers represent. "There is still a question about how long the modernism of the 1950s is going to last," Rosen said in 2011. "The problem is that in order to absorb any difficult style you have to hear the pieces several times. That was true of Mozart, most of whose work was considered difficult at the time ... You really have to hear them well played several times, and there are very few music lovers who've heard a piece by Boulez more than once. That's the fact of it. So will it last? I don't know. Some music doesn't."

At times, critics found that Rosen's intellect weighed too heavily on his playing. A Time reviewer found one of his early recordings to be "clean, fiery and absolutely unsentimental." There is no doubt, however, that his analytical mind formed his distinctive approach to music. And there is little argument that his reputation as a thinker, certainly in his final decades, tended to eclipse his reputation as a pianist. This was perhaps inevitable, since he was one of the pre-eminent music thinkers of his generation, while there were plenty of other pianists to share the pianistic crown.

In 1980, Rosen gave the Charles Eliot Norton lectures at Harvard, later published The Romantic Generation (1995), which analysed the developments in European music from the death of Beethoven in 1827 to the death of Chopin in 1849; it came with a CD recording by Rosen. His other books included works on Arnold Schoenberg and Carter. In addition to his writing and music, he taught at the State University of New York at Stony Brook and the University of Chicago, where he was a Professor Emeritus.

In February this year President Obama presented him with a National Humanities Medal; the citation noted his "rare ability to join artistry to the history of culture and ideas. His writings – about Classical composers and the Romantic tradition – highlight how music evolves and remains a vibrant, living art." In 2011 Rosen said: "The task of the critic is to tell people the way to listen to music so that they get more pleasure out of it through enhanced understanding. Basically, there is no difference between understanding and pleasure. If you listen to a piece of music and it makes sense to you, then you generally like it. I've been so lucky to have had a life devoted to playing music and trying to make sense of it."

Charles Welles Rosen, pianist and writer: born New York 5 May 1927; died New York 9 December 2012.