The twelve-tone system of composition was invented by

The twelve-tone system of composition was invented by Arnold Schoenberg. The twelve-tone technique is a term referring to a type of musical composition that came to replace the old basis of tonality and contribute a new musical structure. This technique involves the use of tone rows, ensuring that all twelve notes are heard without any emphasis on a specific note.

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The "maple leaf rag" (copyright registered on september 18, 1899)[1] is an early ragtime musical composition for piano composed by scott joplin. it was one of joplin's early works, and became the model for ragtime compositions by subsequent composers. it is one of the most famous of all ragtime pieces.[2] as a result joplin was called the "king of ragtime". the piece gave joplin a steady if unspectacular income for the rest of his life.