You cannot simply use a bowl or other curved object as the precise parabolic shape ensures that sound waves are reflected onto one finite focal point. For this build the reflector was obtained ...

the 2D curve of the Lovell Telescope dish is a parabola. It is this shape and structure that allows the telescope to gather incoming radio waves. When the telescope is pointed towards a radio ...

Schematic diagram of a parabolic reflector. Incoming sound is directed to the microphone placed at the focus of the parabola-shaped reflector. The property of the parabolic shape to reflect all sound ...