Sirens went off, and loudspeakers blared: "Duck and cover!
When Morris Pesin ran as an independent for the City Council in 1969, he covered the loudspeaker atop his car's roof with a doghouse.
Cover image: South Korean soldiers draw down a cover from the loudspeakers at a military base near the border between South Korea and North Korea on January 8, 2016 in Yeoncheon, South Korea.
Reports said the US embassy had sounded its "duck and cover" alarm and announced on loudspeakers that the alarm was not a drill.
But "when the speaker cover will be placed over a loudspeaker that generates sound by moving air outside the cover rather than inside, it is irrelevant whether the sheet is acoustically transparent".
At closer inspection, the acoustic lens cover reveals an additional mid-range loudspeaker that delivers perfectly balanced sound throughout the cabin.
Our system of spatialization consisted of four loudspeakers placed back to back (Figure 9) to cover the whole 360-degree range.
The LEDs were located above each loudspeaker (and above the black fabric covering the loudspeakers).
The piece consists of sound generators and a loudspeaker installed in a subway ventilation chamber, which is covered by the grate that pedestrians scurry over.
Calls for resistance rang out through loudspeakers on minarets in Jenin as the tanks advanced under cover of darkness.
