9 Electric, electronic and optical measuring, siqnalling and checking (supervision) apparatus and instruments, in particular electric apparatus and instruments, namely, transducers, arrays, amplifiers and modulators for electroacoustics and parts therefor; apparatus and instruments for recording, transmission and reproduction of audio signals and parts thereof, namely, audio transmitters, high frequency audio receivers, high frequency input modules stero speakers, amplifiers, sounds reproducing equipment; receiving apparatus, namely, high frequency audiovisual receivers, high frequency input modules for providing sound balance; apparatus for the wireless transmission of acoustic information, namely, wireless transmitters; data carriers containing programs for use in database management, use as a spreadsheet and for word processing; software, namely, on floppy discs, tapes, discs for use in database management, for creating and editing music and sounds, to control and improve computer and audio equipment sound quality, software adapted and arranged for operating, installing, testing, diagnosing and managing devices for wireless transmission of acoustic information; small handsets for use in wireless communication, spot recording apparatus, namely, wideband audio and data transmitters with command receivers for audio, video and telephone, return channel audio and data transmitters, diversity program receivers for audio, video and telephone, command audio and data transmitters; headsets for use with microphones, speakers, conference systems, telephones and computers and chin strap receivers as parts of these goods; apparatus for transmission or reproduction of sound; apparatus for conference installations comprised of analog and digital transmitters of audio signals, video signals and data signals, communication headsets and headphones; socket charging apparatus for rechargeable equipment, namely, charging stations, chargers for batteries