Harold Meltzer, a composer who set aside a career as a lawyer to create a highly regarded body of energetic, colorful chamber, vocal and orchestral scores that mixed accessibly melodic themes and rich ensemble textures with the sharp-edged angularity of modernism, died on Aug. 12 in Manhattan. He was 58.

Hilary Meltzer, his wife, said that his death, in a hospital, was caused by respiratory failure, a complication of a variety of medical problems he had withstood since having a stroke in 2019.

Mr. Meltzer, who was also a director (first with David Amato, later with Sara Laimon) of Sequitur, a new-music ensemble, cut an imposing figure at contemporary music concerts in the 1990s and 2000s.

Bespectacled, with wavy hair, he invariably entertained friends during intermissions with wry observations about the music world in general, or the events of the day. Even after his stroke, when he began using a wheelchair, he was determined to maintain something approximating his earlier level of activity, and after only two months of therapy, he appeared as the narrator for his theater work “Sindbad,” a humorous 2005 setting of a Donald Barthelme story that was one of his most frequently performed works.

His music was impossible to pigeonhole, mainly because each work was his response to a different set of challenges. In “Virginal” (2002), for harpsichord and 15 other instruments, he wanted to pay tribute to William Byrd, John Bull and other Elizabethan composers whose works were included in the “Fitzwilliam Virginal Book,” a collection of English Renaissance keyboard pieces. To avoid creating a pastiche, he did not quote from any of their music, focusing instead on the structures and processes (repeating figuration., for example) that made their music distinct.