Ключевые слова: acoustic, alert, announcement, attention, audio, authority, broadcasting, call, clarity, commands, communication, design, device, engagement, equipment, event, expression, functionality, information, loudspeaker, marketing, megaphone, message, modern, new, noise, object, outreach, portable, power, promotion, public, rally, reach, red, sound, speaking, speech, symbol, tool, utility, voice, wave,