The August 15, 1945 radio broadcast announcing Japan’s surrender was commonly called Gyokuon-hōsō.
The Japanese term is often translated as “Jewel Voice Broadcast,” referring to the emperor’s voice. Emperor Hirohito’s recorded address told the Japanese public that the government had accepted the Potsdam Declaration and would end the war. The broadcast was transmitted by NHK at noon Japan Standard Time.
Gyokuon-hōsō is not the same thing as the formal surrender ceremony. The broadcast communicated the decision to the Japanese population, while the legal and military surrender was signed aboard USS Missouri in Tokyo Bay on September 2. The distinction is important because August 15 and September 2 are both associated with Japan’s surrender.
The announcement was unusually significant in Japanese history. Before it aired, most ordinary Japanese people had never heard the emperor speak. The formal language, poor audio quality, and unfamiliar pronunciation meant that many listeners did not immediately understand that Japan had surrendered.