The Hirohito surrender broadcast was replayed from what kind of recording?

The Hirohito surrender broadcast was replayed from a phonograph recording.

Hirohito recorded the Imperial Rescript on the night of 14 August 1945 inside an office bunker connected with the Imperial Household Ministry. Technicians made two recordings because the first attempt was considered too quiet. The second recording became the official version, while the first was retained as a backup.

The recording was not transmitted live from the emperor speaking on air. It was smuggled out of the palace during a failed coup attempt by military officers who wanted to prevent the surrender announcement. NHK engineers then carried it safely to the broadcasting station.

At noon on 15 August, NHK replayed the record to listeners across Japan. The broadcast was historically significant because it was the first time most Japanese civilians had heard their emperor’s voice, even though the formal language and audio quality made the message hard to follow.