Composer Roberto Sierra (Facebook via Roberto Sierra) By PEGGY ANN BLISS Special to The STAR For Roberto Sierra, Puerto Rico’s most venerated living classical composer, this week represents a pinnacle: by Saturday he will have witnessed the world premiere of not one but two of his own creations in less than a week. Hot on the heels of the triumphant unveiling of his “Estudios Latinos” (Latin Studies) in Walt Disney Concert Hall with the Los Angeles Philharmonic Orchestra led by charismatic…
