Sennheiser ew 300 iem Instructions for Use - Page 55

HDX noise reduction O dB - 10 dB - 20 dB - 30 dB - 40 dB - 50 dB - 60 dB - 70 dB - 80 dB - 90 dB - 100 dB - 110 dB O dB - 10 dB - 20 dB - 30 dB - 40 dB - 50 dB - 60 dB - 70 dB - 80 dB - 90 dB - 100 dB - 110 dB Transmitter Receiver Progress you can hear: The evolution wireless series is equipped with HDX, the new Sennheiser noise reduction system that reduces RF interference. It increases the signal-to-noise radio in wireless audio transmission to up to 110 dB. HDX is a wideband compander system which compresses the audio signal in the transmitter in a 2:1 ratio (related to dB) to lift it above the inherent noise floor of the RF link. A 110 dB dynamic range signal is thus transmitted with an effective dynamic range of only 55 dB, which is above the 60 dB noise floor of the RF link. In the receiver the signal is expanded in an identical and opposite way in a 1:2 ratio to restore the original signal, at the same time reducing the RF noise to below the noise floor of the receiver. Giving a radio link with a better signal-to-noise ratio than a CD. HDX has been specially developed for high quality radiomicrophone systems. Note: Only transmitters and receivers that are equipped with HDX can work correctly with each other. If non HDX equipment was mixed with HDX, the dynamic range would be drastically reduced and the transmission would sound blunt and flat. HDX is permanently active and cannot be switched off. 57