Ключевые слова: amplifier, audio, background, black, box, communication, concept, connect, connection, cordless, design, device, digital, electronic, empty, equipment, gadget, hand, holding, listening, loudspeaker, media, mobile, modern, music, musical, nature, object, outdoor, people, phone, play, portable, radio, relaxation, single, smartphone, song, sound, space, speaker, speakers, stereo, system, technology, telephone, travel, volume, white, wireless,