A free concert of Mozart, Bach and Beethoven is being played 24 hours a day on a blighted street corner, not to enlighten the masses but to reduce crime. Police say drug deals, shootings and thefts have dropped since the department mounted a set of speakers and a CD player on an abandoned building and started playing the music in April. There also aren't as many loiterers, who used to number up to 200 on weekend nights on the residential corner in Rosemary Village near downtown. The music, sort of a ``greatest hits'' compilation of the three composers' melodies from three CDs that are played in constant rotation, can be heard clearly up to a block away.