Electrical, electronic, electroacoustic and optical measuring, signaling and monitoring apparatus, instruments and devices , in particular electrical devices and instruments in electroacoustics and parts thereof, devices and instruments for recording audio signals and parts thereof, microphones, filters mains power-supply units, electroacoustic transducers, headsets, earphones, loudspeakers, amplifiers, hearing aids; battery charge devices, parts of the aforementioned goods devices for the transmission of audio and video signals, transmitting and receiving devices, in particular wireless transmitters, pocket transmitters, diversity receivers, antennae, devices for audio transmission, devices for speech therapy infra-red transmitters and receivers, instruments in communications engineering, operator telephone handsets, the aforementioned goods also with active noise compensation, sound proofing devices, in particular in headset form; receiving devices for recording and reproducing electrical signals, in particular audio signals, devices for the wireless transmission of acoustic information, data carriers provided with programs, in particular diskettes, tapes and disks; technical equipment ; cables; audio devices and instruments and parts of all aforementioned goods ; electronic guiding systems for exhibitions, theaters and museums, electronic guiding systems, also multilingual, consisting of receivers and an acoustic reproduction unit; button phones or headphones, electrical and electronic apparatus, like three-dimensional audio reproduction, in particular sound processors