Acoustic couplers; Audio- and video-receivers; Audio interfaces; Audio mixers; Cabinets for loudspeakers; Equalisers being audio apparatus; Headphones; Horns for loudspeakers; Loudspeakers; Megaphones; Microphones; Personal stereos; Portable media players; Recording and playing devices for sound and image carriers; Sound transmitting apparatus; Speaking tubes; Subwoofers; Tape recorders; Virtual reality headsets; Wearable video display monitors