There were many different opinions regarding the best standard. Symphony orchestras were formed in most major cities and performed to a wide audience in the concert halls and on radio. Many of the performers added jazz influences to traditional music, adding xylophones, saxophones and violins, among other instruments.
Progressive rock also represented the maturation of rock as a genre, but there was an opinion among critics that rock was and should remain fundamentally tied to adolescence, so rock and maturity were mutually exclusive. Criticisms over the complexity of their music provoked some bands to create music that was even more complex.