Apparatus for recording, transmission and reproduction of sound or images; radio-broadcasting receivers; clock radios; television receivers; microphones; loudspeakers; headphones, earphones; mini audio systems comprising amplifiers and speakers; audio memory players; mobile audio players; amplifiers; recorders and players of optical discs; recorders and players of magnetic discs; hard disc recorders; video cameras; video monitors; video projectors; audio mixers; audio signal processors; audio and video receivers; remote controllers for audio and video apparatus; wireless audio signal servers and receivers; multi-room wireless audio servers comprising CD-R/RW drives, hard disc drives, tuners, and compressed music encoders and players; wireless audio receivers comprising amplifiers, compressed audio players, and speakers; wireless music system encompassing a wireless transmitter, transmitter cradle and speaker and accessories therefor, to be sold as a unit or separately; dock speakers for mobile audio players; wireless audio signal transmitters; cradles for wireless audio signal transmitters; karaoke machines; pre-recorded discs featuring music or cinematographic films; blank optical discs; personal computers; computer software; personal digital assistants (PDA); routers; conference microphone speakers; teleconference communication terminals; web conferencing cameras; video conference codec boxes; teleconference systems comprising microphones, speakers and communication terminals; telephone sets; cellular phones; large scale integration chips; hardware, software and programs for computer games; electronic publications; downloadable electronic music; metronomes