>> The Rock and Roll Hotel welcomes the country’s first deaf hip-hop group, locals Helix Boyz. Prince Darius and Sho Roc bring an energetic following from nearby Gallaudet University and fun beats that, as you might imagine, you can feel thumping in your body through the speakers. Doors at 8 p.m., $10. >> Daniel Levitin will be at Politics and Prose to discuss his latest book This is Your Brain on Music in conversation…