Was Jascha Heifetz the greatest violinist of the 20th century? His critics carped that all his interpretations sounded the same. It is true that it takes only an instant to recognize his diamondlike precision and powerful tone, but the fact remains that from the time of his U.S. debut and first recordings in 1917, Heifetz set new standards of technical proficiency and coloristic variety that will remain touchstones as long as mortals set bow to strings. As hard as it is to pick one selection from his vast recorded output (currently available in its entirety in RCA's 65-CD Heifetz Collection), this single disc of three 20th-century concertos -- all of which Heifetz helped to popularize -- clearly demonstrates the violinist's ability to use his prodigious gifts to serve the music at hand. No other violinist has captured Sibelius's icy ruggedness, Prokofiev's bittersweet irony, or Glazunov's suave brilliance with such mastery and panache.