The phonograph and radio were two inventions that helped jazz reach even remote locations in the United States.
Phonograph technology had been invented in the late 1800s, and sales of disc records began to be common in the early 1900s.
Radio had been invented by Gabriel Marconi in the 1890s, and by the 1920s was becoming a commercially dominant force. Record sales were impacted by the improved radio technology, but the major record labels were able to continue to sell well until the Depression hit.
