Which country's stereo is acm?

China Acmaudio is a loudspeaker of Aosheng brand, which is a product of Dongguan Aosheng Sound Manufacturing Co., Ltd., established in 2007 and located in Hengkeng Village, Liaobu Town, Dongguan City. Its acm is the voice of China. Audio refers to a set of audio system that combines electrical equipment to produce sound. The development history of audio technology can be divided into four stages: electron tube, transistor, integrated circuit and field effect tube.