Audio- and video-receivers; audio interfaces; audio mixers; batteries, electric; battery chargers; cabinets for loudspeakers; cassette players; chargers for electric batteries; computer peripheral devices; computer software platforms, downloadable, for recording and playing images on devices; surface acoustic wave sensors; horns for loudspeakers; loudspeakers; megaphones; microphones; recording and playing devices for sound and image carriers; sound recording apparatus; transmitters of electr...