Use a high quality
It is essential that the coupling links between the loudspeaker terminals be removed. Avoid potential damage to your amplifier - ensure that all connections are secure and the polarity is correct in all wiring. (See figure 4)
*Be sure that the amplifier is switched OFF and then prepare the two sets of cabling for each 'side' of the system separately. Measure and cut four lengths of cable, two per speaker. Label two of the cable lengths Left LF and Left HF (low frequency and high frequency) then repeat this process for the right pair.
*Undo the speaker terminals and remove the link bar - retain these in a safe place for future use.
*If your amplifier is not equipped with separate output terminals for bass and treble information then, at the amplifier end of the cables, twist the Left LF+ (positive) and the Left HF+ (positive) together. Connect these to the amplifier Left channel positive terminal marked + (plus) or coloured red.
Twist the Left LF- (negative) and the HF- (negative) cables together and connect them to the amplifier Left channel negative terminal marked - (minus) or coloured black.
At the loudspeaker end connect the cables labelled Left LF+ and Left LF- to the left hand loudspeaker LF terminals, ensuring that you note the polarity markings on the cable sheathing.
Then proceed to connect the Left HF+ and Left HF- to the HF terminals on the same loudspeaker.
*Repeat this process to connect the right hand loudspeaker to the amplifier right channel output, once again ensuring that polarity is correct throughout.
*Switch the amplifier on with the volume control set at its lowest setting. Select a favourite source and slowly turn up the volume to a low level. Check that bass and treble information is being reproduced from both speakers- if not, switch off the amplifier and recheck the connections.
If two stereo amplifiers are used, it is recommended that one amplifier supply bass information to left and right loudspeakers and the other, the treble information.(See figure 6)
GRILLES
Special acoustically transparent material is used on the grilles. However, for ultimate fidelity the enthusiast will appreciate the slight improvement in clarity and detail that is achieved by removing the grilles during listening.
CARE OF THE CABINET
Vinyl finished enclosures normally require no more than a wipe with a dry polishing cloth. Fingerprints or other more stubborn marks need only a gentle wipe with a slightly damp cloth.
HOME CINEMA 5.1
Unlike other forms of encoded surround audio, 5.1 offers full bandwidth capability for the surround and centre channels, with the ability to treat the subwoofer as a single discreet channel for special effects playback or, for music applications, as a dedicated low frequency instrument channel. This places new demands on the surround and centre channel loudspeakers in both the mixing environment and the playback environment.
The 5.1 format allows the mix engineer in the recording studio to assign audio information to one or more discreet channels of playback; providing very vivid and exacting localisation for the apparent sound sources in the listening environment. To reliably recreate that accurate localisation during playback, the selection and location of loudspeakers becomes the single most critical issue next to the talent of the mix engineer in the studio.
THE SYSTEM
A fully operational 5.1 system consists of two main front loudspeakers, two rear effects speakers at the rear (usually wall mounted) and a centre channel. The subwoofer provides the .1 part of the system. (See figure 5)
SCREENING
Loudspeaker drive units contain large magnets. These are capable of generating a substantial magnetic field extending a considerable distance beyond the sidewalls of the speaker enclosure. This field can cause picture distortion if the speakers are placed too close to the TV. However, to avoid these colour fringing effects all Mercury models are fully shielded.
FRONT SPEAKERS
The main speaker pair provides much of the delivery of the front soundstage; they should therefore be large enough to handle the power output and dynamics required. Stand mounted speakers can be used for this purpose but the power handling and extra bass extension achievable from floor standing models will add greatly to the overall assurance of the performance. The speakers should be positioned either side of the TV or projection screen placed in line with the screen surface.
CENTRE CHANNEL SPEAKERS
As the main effects speaker for the front soundstage, the critical factor in its performance is placement. In all cases the centre channel speaker should be placed as near to the TV screen as possible; effective shielding will allow placement on top of the TV itself. If the shape of the top of the TV casing will not allow a stable placement it can be shelf mounted just above. The viewing position when seated determines the ideal mounting height, but in all cases this should be as close as possible to ear height.
As with the main speakers the front baffle panel should be as near as possible in line with the screen surface.
REAR EFFECTS SPEAKERS
The integrity of the special effects soundstage created by the source material will be compromised if the speakers are installed on the sidewalls, for that reason they should always be placed behind the main viewing position.
The placement of floor standing speakers at the rear should mirror as near as possible the location of the front pair and 0.5 metres (20 inches) from the rear wall.
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