Amplifiers; Amplifiers being audio apparatus; Audio amplifiers; Sound amplifying apparatus; Stereo amplifiers; Audio speakers; Audio speakers for home; Car speakers; Speakers for computers; Public address speaker systems; Personal stereo speaker apparatus; Karaoke equipment; Karaoke apparatus; Graphic decoders for use with video karaoke systems; Graphic decoders for use with audio karaoke systems; Coders for use with karaoke apparatus