Amplifier; radios; compact disc players and recorders; digital video disc players and recorders; laser disc players and recorders; audio cassette players and recorders; audio speakers; subwoofer audio speakers; stereo receivers; audio and video receivers; signal converter used to convert digital signals to analogue signals, analogue signals to digital signals and voice to analogue and digital signals; power conditioners used to protect electrical equipment; speaker components, namely, tweeters, midrange, crossover and tuner; audio and video cables