Public address system
device · 1915 · Electric age
Loudspeakers for an audience.
What it is made of
- Loudspeaker — has part. Loudspeakers.
- Amplifier — has part. Amplifiers.
Principles and materials it uses
- Steel — is made of. Loudspeaker housings are metal.
Where it is used
- Stadium — is part of. Sound.