Sound amplification by stimulated emission of radiation phenomenon, known as the Larsen effect, is the result of a positive feedback. In general, every oscillator consists of three main parts. These are the power source or pump, the amplifier and the positive feedback leading to the output. The corresponding parts in a SASER device are the excitation or pumping mechanism, the active (amplifying) medium, and the feedback leading to acoustic radiation. Pumping can be performed, for instance, with an alternating electric field or with some mechanical vibrations of resonators. The active medium should be a material in which sound amplification can be induced. An example of a feedback
The Sound of a Voice The Sound of a Voice The Sound of a Voice is a 1983 play by American playwright David Henry Hwang. Hwang's fifth play, it is an original ghost story inspired by Japanese folk stories, films, and Noh theater. The play was first produced as part of the production "Sound and Beauty" on November 6, 1983 Off-Broadway at the Joseph Papp Public Theater. It was directed by and featured John Lone. Composer Philip Glass and Hwang adapted it for the opera "The Sound of a Voice" in 2003. That same year, Susan Hoffman directed a film adaptation entitled "Sound of a