In the late nineteenth century, ^5,000 pianos were sold in the United States each year and, with over half a million youths learning to play the instrument, there was a huge demand for sheet music  .Indeed the demand was so huge that publishers rushed to enter the profitable market.During the last fifteen years of the century, many publishers began to set up shops in New York, the center for the production of the musical arts By the turn of the nineteenth century many important publishers had their offices on 28thStreet between Broadway and 5th Avenue, and this Is the area that became known as Tin Pan Alley.It was here that publishers adopted new, aggressive business practices and marketing techniques to achieve great sales. How it became to be known by that name is unclear, but the general opinion is that it is down to a visiting journalist by the name of Monroe Rosenfeld.He described the area as being drowned in the noise coming from the producers' offices, sounding as though hundreds of people were hitting tin pans .He used it several times in his newspaper articles in the early twentieth century and the term stuck.With time this name was popularly embraced and many years later it came to describe the U.S.music publishing industry in general. The start of Tin Pan Alley is usually dated to about 1885,.but the end of Tin Pan Alley is less clear-cut .Some date it to the start of the Great.Depression in the 1930s when the phonograph  and radio replaced sheet music, as the driving force of American popular music, while others consider Tin Pan Alley to have continued into thel950s when earlier styles of American popular music were upstaged   by the rise of rock & roll. There's a plaque on the sidewalk on 28th Street in honor of the influence of Tin Pan Alley on American popular culture, but the buildings that were home to the legendary Tin Pan Alley publishers and songwriters are up for sale and may be torn down to make room for modern high-rise buildings. We can learn from the passage that   _  .
the term " Tin Pan Alley" was perhaps first used by Rosenfeld. the old shops of Tin Pan Alley will be well protected. Tin Pan Alley got its name in the early nineteenth century. there were once some factories in Tin Pan Alley