"of all time, Woodstock, has seen its concert footage shown the world over. That same year in New York, over 300,000 people attended the predominantly African-American concert series known as the Harlem Cultural Festival. The filmed performances of some of the most important artists in black music history sat in a basement for five decades, only to finally be seen in “Summer Of Soul (…Or, When The Revolution Could Not Be Televised),” a documentary by first-time director Ahmir-Khalib “Questlove"