Focal CHORA 806 Manuel D'utilisation page 14

CHORA
™
U s e r m a n u a l
14
Connections (fig.E)
Chora connectors provide reliable, multi-purpose contacts for stripped cables (up to 4mm diameter), fork
terminals or banana connectors. It is imperative to respect the connector polarity of both the loudspeaker
and the amplifier. The connector marked "+" must be connected to the positive output on the amplifier and
the connector marked "-" must be connected to the negative terminal . Stereo image and bass perception
would be seriously compromised if these conditions are not respected. Choose good quality cables with a
cross-section appropriate to their length: your retailer will be able to advise you.
Positioning (fig. F, G, H)
These loudspeakers have been designed to deliver the most faithful reproduction of all kinds of music or
home cinema programmes. Nonetheless, we recommend following these simple rules to optimise their
performance and to warranty good tonal balance and a realistic sound image.
The loudspeakers should be positioned symmetrically, facing the listening area, ideally forming
an equilateral triangle with it. However, these distances may be adjusted to find the ideal compromise
according to the design of your interior (fig. F).
The loudspeakers should be positioned at the same height, in the same horizontal plane. Ideally, the
tweeter should be positioned at the same height as the listener's ears in the usual listening position (fig. G).
Do not position your loudspeakers too close to a corner of the room and do not place them too close
to a wall. This will induce some unwanted room resonance and artificially increase bass response. On the
other hand, if the bass level is considered to be insufficient, you could try moving the loudspeakers nearer
a wall to re-balance the bass level (fig. H).
Optimisation (fig. I)
For perfectionists, here is a formula for optimal positioning:
If A is the distance from the centre of the woofer to the nearest floor or wall, B is the distance to the next
closest floor or wall, and C is the greatest distance (A < B < C), the equation B = AC defines the ideal
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loudspeaker position.
• Example:
If the centre of the woofer is 20" (50cm) away from the rear wall (A) and 24" (60cm) above the floor (B),
then the side wall will be ideally 28" (72cm) away [C = B ⁄ A = 28" (72cm)].
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Recommendations for use
The behaviour of the loudspeakers depends on the acoustics of the listening room, on the correct positioning
of the loudspeakers within the room, and on the position of the listener.
It is possible to tweak each of these parameters to obtain or improve a desired effect.
Stereo perception is imprecise and poorly centred: try moving the loudspeakers closer together and/or
have them facing the listening point:
The sound is harsh, aggressive: the acoustics of your listening room are probably too reverberant. Consider
using sound-absorbing materials (carpets, upholstered furniture, tapestries, curtains, etc.) and sound-
reflecting materials (furniture) to absorb or diffuse resonance.
The sound is "flat", strangled: there are too many sound-absorbing materials in the room, the sound is
soaked up, it has no relief. Look for the best compromise between sound-absorbing and sound-reflecting
materials in your room.
In general, aim to have a reflective wall behind the loudspeakers for the sound to develop correctly. The wall
behind the listening area, on the other hand, should ideally be sound-absorbing to avoid rear reflections
"contaminating" the stereo image.
Furniture can be judiciously placed near the side walls of the room to diffuse sound waves and ensure
certain frequency ranges are not excited, particularly in the midrange (suppression of flutter echoes).