KEF Audio 209, 208 manual Movie only setup through the LFE input

Movie only setup through the LFE input.

This dedicated line level input is specifically for the LFE (Low Frequency Effects) output from a surround sound A/V processor. Please note that single ended (phono) or balanced (XLR) connections are available, however, they must not be used simultaneously. The LFE input to the subwoofer will not be affected by the Frequency or Slope controls which apply only to the Left and Right channel line inputs.

Once your subwoofer is connected and powered up it needs to be integrated into your home cinema system. To do this you will need to follow the set-up procedure for your surround sound processor. Set the subwoofer level to near maximum and the phase to 0. In the surround sound processor’s speaker menu, ensure that the subwoofer is set to ‘on’. If using smaller satellite speakers then set the speaker size to ‘small’. KEF would recommend starting with the ‘small’ setting if you are unsure.

If you are using full range speakers set the speaker size to ‘large’. Use the processor’s controls to adjust the level of the subwoofer at the same time as setting each of the channel levels.

Music only setup through the Left/Right inputs.

To increase the low-frequency extension of your existing stereo speakers connect the amplifier’s line level outputs to the subwoofer Left and Right line level inputs. If line level outputs are not

available then connect the Left and Right amplifier high level speaker outputs to the speaker inputs of the subwoofer. Once the subwoofer is connected and the power is switched on it needs to be acoustically integrated into your existing system. To do this you will need to use the Level, Frequency and Phase controls.

First select the subwoofer low-pass filter slope to match your main speakers. For a bass reflex speaker the slope should be set to 24dB/octave. This applies to all the KEF Reference Series loudspeakers. For a closed box loudspeaker, however, the slope should be set to 12dB/octave.

Select a piece of music that you are familiar with which has a constant, repetitive bass line. Start with the Level and Frequency controls at the middle positions and the phase control set to

0.Adjust the level control until you are happy with the low frequency levels when compared with the main speakers. Now adjust the Frequency control so that there is no obvious change in the level of the sound from very low frequencies to higher frequencies. Adjust the polarity and the phase control to achieve the smoothest integration between the subwoofer and the main speakers. KEF recommend you take some time making fine adjustments to the controls, whilst listening to a varied selection of music, until you are satisfied with the sound balance.

Combined movie and music setup.

The Reference Series 208 subwoofer can be used for both main speaker low frequency extension and the LFE channel reproduction for a surround sound system.

Set the subwoofer up as described in section ‘Music Only Setup’. With the subwoofer correctly set up for stereo use, connect the LFE output from your surround processor to the LFE line level input of the subwoofer. Without making any adjustments to the subwoofers controls, including the volume level, follow the set-up procedure on your surround processor to adjust the subwoofer volume level (as described in section ‘Movie Only Setup’).

Connecting to the speaker inputs (high level).

Speaker level or line level inputs are available to allow flexibility in set-ups for the Left and Right inputs. The specific LFE input is line level only to interface with an A/V processor.

The speaker input terminals will accept bare wire, spade or 4mm connectors. Most good quality loudspeaker cables have some indication, such as colour coding or ‘ribbing’ on the insulating material, indicating which conductor is ‘+’ or positive. Connection to the subwoofer can then be made as follows:

The left channel amplifier output terminal marked ‘+’ or coloured RED connects to the left subwoofer speaker input terminal marked ‘+’. The left channel amplifier output terminal marked

‘-’ or coloured BLACK connects to the left subwoofer speaker input terminal marked ‘-’. Similarly, these instructions should be followed for making connections between the right channel amplifier output and the right subwoofer speaker input terminals. Correct polarity, or phase, is vital to the proper operation of the system.

Bare wire connections are the simplest to achieve and involve stripping 12.5mm (1.2in.) of insulation to expose the loudspeaker wire core. (You should twist together, using clean fingers, the ends of each multi-stranded core prior to the next stage to ensure a good signal contact). Having unscrewed the lower terminal cap, push the wire through the exposed hole in the terminal body and screw the cap down tightly. Make sure that no stray strands come into contact with the opposite terminal; this could cause a short circuit between the terminals and may damage your amplifier.

Be aware that a higher quality run of cable will always give a more rewarding presentation than multiple runs of an inferior cable.

Poor quality cables can seriously compromise the overall sound of your hi-fi system.

KEF recommends that high quality loudspeaker cable be used for connecting to your Reference Series Model 208 subwoofer high level inputs. It is good practice to keep the cables as short as possible.

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