JOAQUIN RODRIGO, the Spanish composer who died July 6, 1999, at the age of 97, was a rarity among contemporary composersâa composer who was not only respected, but beloved. His compositions, with their bright instrumentation and vivid evocations of Spain, won the affections of music lovers all over the world, and one of them, the "Concierto de Aranjuez," became the most popular guitar concerto ever written.