Acoustic conduits; Acoustic couplers; Audio- and video-receivers; Audio equalizer apparatus; Audio interfaces; Audio mixers; Cabinets for loudspeakers; Ear pads for headphones; Earphones; Electronic book readers; Headphones; Horns for loudspeakers; Microphones; Personal stereos; Portable media players; Recording and playing devices for sound and image carriers; Sound recording apparatus; Sound transmitting apparatus; Subwoofers; Tape recorders