Daniel Wolf's Renewable Music blog

"It's often overlooked, but in the common practice era, music theatre, both opera and ballet, was a major source for innovation while concert music was largely a domain for the conservation and perfection of established forms. Opera and ballet, while never dispensing altogether with conventions of their own (after all: singers must breath and dancers must land after leaping), were natural testing grounds for new possibilities in orchestration, texture, figuration, harmony, and even spatial effects. In the music theatre, the attraction of finding new and dramatically useful effects simply overruled any prior constraints on form or content."

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