alert
announce
announcement
art
audio
background
bright
broadcast
broadcasting
bullhorn
color
colorful
communicate
communication
concept
contour
design
equipment
flat
glowing
horn
icon
illustration
isolated
light
line
linear
lineart
loud
loudspeaker
megaphone
message
music
neon
object
outline
public
scream
shout
shouting
sign
sound
speak
speaker
speech
symbol
voice
volume
warning