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 February 8, 2017 at 4:01 pm #8219 DarenKeymaster This is lovely playing Quetscher! I was lucky enough to try out the Labourdette prototype in its early stages. I remember the reeds were slightly bigger than the Clavietta, and the angle of them shifted 90 degrees for a more efficient airflow.