Sennheiser W300 manual Additional information, HDX noise reduction, Wireless transmission systems

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Additional information

HDX noise reduction

RF link

Inherent noise

of the RF link

Transmitter

Receiver

Progress you can hear:

The evolution wireless G2 series is equipped with HDX, the Sennheiser noise reduction system that reduces RF interference. It increases the signal-to- noise ratio in wireless audio transmission to more than 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.

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 bluntandflat.HDX is permanently active andcannot be switchedoff.

Wireless transmission systems

With the ew 300 G2 series, Sennheiser puts an end to cable tangles and enables complete freedom of movement. The systems operate exclusively in the UHF band. UHF transmission is extremely reliable and is far less prone to interference than the overcrowded VHF band – harmonics from mains units, fluorescent tubes, refrigerators, computers, etc. are virtually eliminated. Also indoor propagation of UHF radio waves is better than VHF so that the RF power can be kept low – this is also an advantage when using multi-channel systems. Finally, UHF frequency ranges are being approved all over the world for radiomicrophone usage – in some countries licence-free.

There are two transmitter versions: The hand-held transmitter is a complete radiomicrophone in a single unit, the bodypack transmitter can accept a wide range of inputs including: omni-directional or cardioid clip-on microphones, head-worn microphone, guitar/instrument direct input and auxiliary units via the optional CL 2 line input cable.

 

Correct adjustment of transmitter sensitivity is vital. Too high and you get

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overmodulation and distortion, too low and you get undermodulation and a

 

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Contents W300 Thank you for choosing Sennheiser Contents Evolution wireless series ew 300 G2 Channel bank systemAreas of application Safety instructionsSystem variants Delivery includesOverview of operating controls EM 300 G2 rack-mount receiverSK 300 G2 bodypack transmitter SKM 300 G2 radiomicrophone Mute display Transmitter battery status indicationIndications and displays on the receiver Modulation displayDiversity display Operation and battery status indicationIndications and displays on the transmitters Button backlightingAF peak indication SK 300 G2 only Display backlightingPreparing the components for use Connecting the antennasConnecting the mains unit Mounting the receiver feetRack adapter and antenna mount Connecting the amplifier/mixing consoleService interface Bottom sides of the receivers Inserting and charging the accupack Connecting the microphone/line cableInserting and replacing the batteries Attaching the bodypack transmitter to clothing Attaching the microphonesPositioning the microphones Changing the microphone head Switching the rack-mount receiver on/off Using the componentsSwitching the components on/off Switching the bodypack transmitter on/offMuting the SK 300 G2 bodypack transmitter Activating/deactivating the lock modeMuting the transmitters Muting the SKM 300 G2 radiomicrophoneOverview of menus Operating menuButtons Working with the operating menu Adjusting a settingStoring a setting Getting into the operating menuExiting the operating menu 01 786.300 MHz Operating menu of the receiverMHz Low High Main FrequencyPilot OffExit Operating menu of the transmittersBank Switching between the channels in a channel bank Adjustment tips for the operating menuSwitching between channel banks Starting the scan Scanning the channel banks for free channels EM 300 G2 onlyDisplaying the last scan result Releasing locked channelsAdjusting the sensitivity transmitters only Multi-channel operationIMPORTANT! Notes Adjusting the audio output level EM 300 G2 onlyAdjusting the squelch threshold EM 300 G2 only Selecting the standard display EM 300 G2 rack-mount receiverLoading the factory-preset default settings Entering a nameAdjusting the contrast of the graphic display EM 300 G2 only Exiting the operating menuIf problems occur Error checklistRecommendations and tips Care and maintenance For multi-channel operationHDX noise reduction Wireless transmission systemsAdditional information Pilot tone squelch SquelchDiversity reception Field strength-dependent squelchReceiver SpecificationsSystem Microphones Onnector assignmentTransmitters Microphone headsPage Accessories CE Declaration Conformity Warranty regulationsManufacturer declarations Batteries or rechargeable batteries