Controlling the transistor requires an intermediate step converting the sound to heat. In my book, this isn't really an 'acoustic' transistor. Phononic transist

Controlling the transistor requires an intermediate step converting the sound to heat. In my book, this isn't really an 'acoustic' transistor. Phononic transistors have been proposed though[0]. Phononic transistors have been built, albeit with some magnets, but merely for their nonlinear mechanical properties[1] [0] https://arxiv.org/abs/1509.00679 https://arxiv.org/abs/1509.00679 [1]https://www.pnas.org/content/114/18/4603 https://www.pnas.org/content/114/18/4603