Abstract: A body motion controlled audio playing device is disposed with a sensing switch that can be covered in a non-contact way to selectively enable such functions as startup, shutdown, mute, and volume adjustment.

Abstract: A body motion controlled audio playing device is disposed with a sensing switch that can be covered in a non-contact way to selectively enable such functions as startup, shutdown, mute, and volume adjustment.

Abstract: A ripple digital amplifier system includes one or multiple amplifier, one or multiple I/O process unit, and one or multiple transmission unit; the I/O process unit being built in the amplifier and including an audio receiving unit, an audio signal converting unit, an audio and output unit; and the transmission unit being disposed between every pair of amplifiers to transmit audio to each amplifier.

Abstract: A composite cable assembly comprises optical fiber and metal wire, having a composite connector at each end of the cable. The connector houses the optical fiber at its core, with an elongated cylinder protruding from a protective grip forming an insertion guide and functioning as an electrical conductor. An opto-electro adaptor has an open passageway for connector insertion, an optical device at the end of the passageway, an elongated cylinder as insertion guide and electrical conductor, a sheet metal as electrically conductive element.

Abstract: An optical digital audio system has an input receiver module that connects with one or multiple output speaker module(s) via optical fiber cable(s). The input receiver module has an audio signal receiving device, an amplifier and control device, one or multiple digital-to-optical converter(s), and one or multiple optical signal transmitter(s). The output speaker module has an optical signal receiver, an optical-to-digital converter, a digital signal amplifier, a digital-to-analog converter, and a speaker.