Home / Forums / Melodica technique / Sonny Boy Williamson Apparently Covering the Outlet Slots on His Harmonica / Reply To: Sonny Boy Williamson Apparently Covering the Outlet Slots on His Harmonica Reply To: Sonny Boy Williamson Apparently Covering the Outlet Slots on His Harmonica January 17, 2017 at 8:06 am #8138 jazzman1945Participant SBW doesn’t block the selected sounds, he makes them sound more sharply.