Dayton Audio TD20F-4 3/4" Soft Dome Neodymium Tweeter 4 Ohm Dayton Audio's TD20F-4 3/4" silk dome tweeter incorporates an optimized diaphragm that combines low mass, superb damping, and a carefully calculated dome profile offering an exceptionally flat frequency response. This, along with the low distortion neodymium motor system, ensures that high frequency content is reproduced as transparently as possible.