The technical demands on the soloist are formidable, with generous use of multiple stopping, broken chords, rapid scale passages, and rhythmic variation. The difficulty may to some extent be attributed to the composer's being chiefly a pianist.[citation needed]

Nevertheless, Brahms chose the violin-friendly key of D major for his concerto. Since the violin is tuned G'D'A'E, the open strings, resonating sympathetically, add brilliance to the sound. For the same reason, composers of many eras (e.g. Bach, Mozart, Beethoven, Schumann, Tchaikovsky, Sibelius, Prokofiev, Korngold and Khachaturian) have written violin concertos in either D major or D minor. (Wikipedia)