Marian Anderson is twice a legend: classical singer, and civil rights icon. When Toscanini first heard Marian Anderson in 1935, he said: "A voice like hers is heard only once in a hundred years." But four years later, she was forbidden to sing at Constitution Hall in Washington DC because she was a black woman. In protest, First Lady Eleanor Roosevelt arranged a concert at Lincoln Memorial, which drew a crowd of 75,000. On Sunday, February 17, the 2013 VocalEssence "Witness" concert pays tribute to Marian Anderson's legacy. Classical MPR's John Birge learned more from the singer who'll evoke the spirit of Anderson, Marlissa Hudson.