Rammellzee, who died in 2010 at age 50, is most famous for his hit 1983 K-Rob team-up "Beat Bop," but the graffiti artist and MC's…

Hip-hop's first 20 years were built on decibels. A Bronx-bred arms race over speaker size, rocking without a band, "my JVC" vibrating the concrete, pumping…