With his emphasis on quiet sustained sonorities and textures, Gaber is counted among the early American minimalist composers, and considered to be a forerunner of drone and spectralism.
[1] His best known recorded composition, The Winds Rise in the North, has been called by musician Keith Fullerton Whitman "one of the holy grails of minimalism in music in the 20th century.
"[2] In 1978, he stopped composing, moved from New York City to San Diego, California, and began creating photo-collages, mixed media collages, paintings, and pen-and-ink works he called graphic music.
However, in 1993 he started work on Die Plage (The Plague), an art-historical narrative of Germany from the Weimar Republic to the end of World War II, completing it in 2002.
[5][6] Horace Reisburg, Gaber's music teacher at New Trier High School from 1958 to 1961 in Winnetka, Illinois, encouraged him to continue his studies at the Aspen Institute with Darius Milhaud in the summer of 1961.
By 1985, his experiments with photomontage led to acquisition of one of his works and its inclusion in an exhibit by the Museum of Photographic Arts[11] in San Diego's Balboa Park, California.
Art critic Jonathan Saville, writing for the San Diego Reader, wrote: In experiencing Die Plage (The Plague), you first focus on the emotion-charged content of the pictures, the Nazi arrogance, the Jewish suffering.
After awhile, you become aware of the remarkable artistry displayed in each of the canvases, the powerful composition, the dramatic treatment of darks and lights, the fabulously expressive use of such aesthetic elements as repetition, contrast, density, patterning and texture, where even the graininess of the enlarged photos is given an artistic purpose.
The heart of the show is made up of four continuous sections, whose subjects progress chronologically from the promising dynamism of the Weimar Republic through the depravities of the Nazi regime.
"[7][9] Harley Gaber resumed composing in 2008, after receiving a commission from William Hellerman of the Downtown Ensemble, resulting in Webern's Gambit, a multi-media work for film and cello.
It associated film imagery, including old German footage and recordings, with a cello part derived from pitches in a movement of Anton Webern's Piano Variations.
A panel on Gaber's life and works was moderated by composer Eric Richards, with discussants Paul Paccione, Ned Sublette and Bill Hellerman.