"Ministry staff please be aware, Muggle-born hearings are commencing in the Courtroom areas of the Department of Mysteries. Dolores Umbridge presiding."
—An announcement over this tannoy[src]

This tannoy was located in the British Ministry of Magic Headquarters, and was used to relay public messages throughout the building. On 2 September, 1997, it relayed that the trials on suspected Muggle-borns were beginning in the courtrooms on Level 10.