Bowers & Wilkins 803, 804 Français, Garantie limitée, Fine tuning, Running-inperiod, Aftercare

Models: 803 804

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if the links are left in place, may cause damage to the amplifier by shorting its output terminals.

Fine tuning

Before fine tuning, double check that all the connections in the installation are correct and secure.

Moving the speakers further from the walls will reduce the general level of bass. Space behind the speakers also helps to create an impression of depth. Conversely, moving the speakers closer to the walls will increase the level of bass.

If the bass is uneven with frequency it is usually due to the excitation of resonance modes in the room. Even small changes in the position of the speakers or the listeners can have a profound effect on how these resonances affect the sound. Try mounting the speakers along a different wall. Even moving large pieces of furniture can have an effect.

If the central image is poor, try moving the speakers closer together or toeing them in so they point at or just in front of the listeners. (figure 4)

If the sound is too harsh, increase the amount of soft furnishing in the room (for example use heavier curtains), or reduce it if the sound is dull and lifeless.

Test for flutter echoes by clapping your hands and listening for rapid repetitions. Reduce them by the use of irregular shaped surfaces such as bookshelves and large pieces of furniture.

Ensure the speakers stand firmly on the floor. Whenever possible fit the spike feet supplied after you have optimised the positioning. They are designed to pierce through carpeting to the floor surface. Initially, screw the lock nuts fully onto the spikes and screw the spikes fully into the threaded inserts in the base of the speaker. If the cabinet rocks, unscrew the appropriate spikes until the speaker stands firmly on the floor and lock them in place by tightening the lock nuts against the base. If you do not have a carpet, use a protective disc under the spikes to protect the floor surface.

For the most discerning listening, remove the cloth covered grille as described below in the section “Aftercare”. The tweeter is very delicate and its grille should be left in position for protection. For this reason the grille retaining ring is designed to provide the optimum acoustic environment for the unit and the response is less smooth with the grille removed.

Running-in period

The performance of the speaker will change subtly during the initial listening period. If the speaker has been stored in a cold environment, the damping compounds and suspension materials of the drive units will take some time to recover their correct mechanical properties. The drive unit suspensions will also loosen up during the first hours of use. The time taken for the speaker to achieve its intended performance will vary depending on

previous storage conditions and how it is used. As a guide, allow up to a week for the temperature effects to stabilise and 15 hours of average use for the mechanical parts to attain their intended design characteristics.

Ancillary equipment

Speakers of this ability deserve signals of the highest quality. Choose your electronic equipment and interconnecting cables with care. We can give guidance on what to look for when choosing ancillary equipment, but cannot recommend specific items. The standards of such products are improving all the time and your dealer will be able to demonstrate a variety of suitable up-to-date products.

In the specification we recommend a range of amplifier powers. The higher figure is defined by the power handling capability of the speaker. When calculating the power handling, it is assumed that the amplifier is not run into clipping, which distorts the frequency power spectrum of the signal, and that the signal is normal programme material. Test tones from oscillators and the like are not applicable. The lower figure is the minimum we consider necessary to achieve reasonable listening levels without audible distortion in the smaller room (less than 60 m3 or 2000 cu ft). The higher the power you use, the less likely you are to experience amplifier clipping. You can often tell how good an amplifier is at driving complex speaker loads by looking at its power rating into both 4Ω and 8Ω loads. The nearer the ratio is to 2:1 the better, as it indicates a good current capability.

In order to reduce the effect the cable has on the frequency response of the speaker to inaudible levels, the impedance of the cable at all frequencies (measuring both positive and negative conductors in series) should be kept as low as possible and certainly below 0.1Ω. At low frequencies, the DC resistance of the cable is the dominant factor and you should choose a gauge of wire sufficient to achieve the impedance requirements over the length of cable you need to use. At mid and high frequencies the inductive component of the impedance can dominate the DC resistance. This and other properties influenced by the detailed construction of the cable become important. Ask your dealer for advice on the best cable for your needs.

Aftercare

The cabinet surface usually only requires dusting. If you wish to use an aerosol cleaner, remove the grille first by gently pulling it away from the cabinet. Spray onto the cleaning cloth, not directly onto the cabinet. The grille fabric may be cleaned with a normal clothes brush whilst the grille is detached from the cabinet.

The surface of the tweeter housing will benefit from the use of an anti-static cleaner. Do not attempt to remove the tweeter grille.

Avoid touching the drive unit diaphragms, especially the tweeter, as damage may result.

Français

Garantie limitée

Cher Client,

Bienvenue à B&W.

Ce produit a été conçu et fabriqué en vertu des normes de qualité les plus rigoureuses. Toutefois, en cas de problème, B&W Loudspeakers et ses distributeurs nationaux garantissent une main d’œuvre (exclusions possibles) et des pièces de rechange gratuites dans tout pays desservi par un distributeur agréé de B&W.

Cette garantie limitée est valide pour une période de cinq ans à compter de la date d’achat ou une période de deux ans pour les composants électroniques, y compris les haut-parleurs amplifiés.

Conditions

1La garantie est limitée à la réparation de l’équipement. Les frais de transport ou autres, les risques associés à l’enlèvement, au transport et à l’installation des produits ne sont pas couverts par cette garantie.

2La garantie est exclusivement réservée au propriétaire d’origine et ne peut pas être transférée.

3Cette garantie ne s’applique qu’aux produits faisant l’objet de vices de matériaux et/ou de construction au moment de l’achat et ne sera pas applicable dans les cas suivants :

adétériorations entraînées par une installation, connexion ou un emballage incorrect,

b.détériorations entraînées par un usage autre que l’usage correct décrit dans le manuel de l’utilisateur, la négligence, des modifications ou l’usage de pièces qui ne sont pas fabriquées ou agréées par B&W,

c.détériorations entraînées par un équipement auxiliaire défectueux ou qui ne convient pas,

d.détériorations résultant de : accidents, foudre, eau, chaleur, guerre, troubles de l’ordre public ou autre cause ne relevant pas du contrôle raisonnable de B&W ou de ses distributeurs agréés,

eLes produits dont le numéro de série a été modifié, effacé, éliminé ou rendu illisible,

f.les produits qui ont été réparés ou modifiés par une personne non autorisée.

4Cette garantie vient en complément à toute obligation juridique nationale / régionale des revendeurs ou distributeurs nationaux et n’affecte pas vos droits statutaires en tant que client.

Comment faire une réclamation en vertu de la garantie

Veuillez respecter la procédure ci-dessous, si vous souhaitez faire une réclamation sous garantie :

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Bowers & Wilkins 803 Français, Garantie limitée, Fine tuning, Running-inperiod, Ancillary equipment, Aftercare, Conditions