Bowers & Wilkins ASW 2500 All applications, Taking care of the subwoofer, Français Avertissements

the relative positions of all the speakers in the installation.

Set the system up in the preferred position and play some programme with a steady bass content. The optimum setting for the LOW-PASS FREQUENCY depends on several variables; the bass performance and power handling of the satellite speakers, the number of subwoofers used and their position relative to the satellite speakers. The range 80 – 90Hz is a good starting point for the LOW-PASS frequency. Unless two subwoofers are used to preserve separate right and left channel information and are sited close to the relevant satellite speakers, using a higher cut-off frequency may compromise the stereo image and should only be considered if the bass performance of the satellite speakers is particularly limited.

At each setting of the cut-off frequency, listen with the phase switch in both positions. The correct one is that which gives the fullest bass and that will depend on the bass characteristics of your satellite speakers and the relative distances of the subwoofer(s) and the satellite speakers to the listeners. When using more than one subwoofer, ensure that each one has its cut- off frequency and phase switch set the same way.

Set the loudness of the subwoofer relative to the satellite systems to your liking. Use a wide variety of programme material to get an average setting. One that sounds impressive on one piece may sound overpowering on another. Listen at realistic levels as the perception of balance varies with sound level.

Home theatre

The situation with home theatre is somewhat different from 2-channel audio. The subwoofer (LFE) signal is a separate channel rather than an extension of the signal to the satellite speakers. The LOW-PASS filter is switched out, because the decoder provides all the filtering for any speakers set to “small”. However, the position of the phase switch must still be assessed. Normally the phase will be set to 0˚, but if the subwoofer is positioned at a distance significantly different from the other speakers, or the power amplifier driving the other speakers happens to invert the signal, the 180˚ position may be preferable. Listen with the switch in both positions and choose the one that gives the fullest sound. If there is little difference, leave the switch at 0˚.

Decoders normally have a calibrated noise signal that can be used to set the relative levels of all the speakers, making the task somewhat more straightforward than for 2-channel audio. However, do not be afraid to alter the settings to your personal preference. It is all too easy to get carried away with the capabilities of the subwoofer, especially with some special low- frequency effects. Often a more realistic portrayal, and one more satisfying in the long term, is to be had by setting the subwoofer level lower that the standard calibration level.

All applications

If you get problems with lumpy bass – if certain bass notes are exaggerated more than others – then you probably have a room interface problem and it is worth experimenting with the placement of the subwoofer. What may seem like small changes in position – 15cm (6in) or so

–can have a profound effect on the sound. Try raising the subwoofer clear of the floor as well as lateral movement. The use of multiple subwoofers can smooth the effects of room resonances, as each subwoofer will tend to excite resonances at different frequencies. If you alter the relative distances from the subwoofer(s) and satellite speakers to the listeners appreciably, reassess the phase switch setting. You should also check the level setting of the subwoofer (using either the decoder output levels or the volume control on the subwoofer amplifier as appropriate), but only after setting the phase correctly.

Taking care of the subwoofer

The cabinet of the subwoofer may be cleaned by dusting with a dry cloth. If you wish to use an aerosol cleaning spray, do not spray directly on the cabinet; spray onto the cloth. Remove the grille first so that the cloth does not become stained, but be careful not to disturb the drive unit. The grille itself may be cleaned using a soft brush.

Do not use the subwoofer as a table. When in use, objects left on top of the subwoofer are liable to rattle. In particular, avoid the risk of liquids being spilled (eg from drinks or vases of flowers).

If the system is taken out of use for a long period, disconnect the subwoofer from the power supply.

FRANÇAIS

AVERTISSEMENTS:

ATTENTION: les versions 120V de ce produit sont livrées avec un cordon d’alimentation avec connecteur polarisé. Pour éviter les chocs électriques, introduisez la lame la plus large de la fiche dans la borne correspondante de la prise et poussez jusqu’au fond.

Pour éviter tout risque d’incendie ou d’électrocution, n’exposez jamais cet appareil à la pluie ou même a l’humidité.

Observez tout signe anormal pouvant provenir du subwoofer lui-même.

N’ouvrez jamais l’enceinte et ne sortez pas l’amplificateur de son logement ; vous n’y trouverez aucun réglage utile. En cas de problème renseignez-vous, préalablement à toute intervention, auprès d’un véritable revendeur spécialiste de la marque B&W.

Assurez-vous, en premier lieu, que la tension indiquée sur l’appareil correspond bien a celle de votre réseau électrique.

Les fusibles d’alimentation se trouvent sur le panneau du module d’amplification. En cas de remplacement, n’utilisez jamais de fusibles d’un type différent ; vérifiez que les valeurs indiquées sur les nouveaux fusibles sont parfaitement identiques à celles qui figurent sur les modèles d’origine.

Cet appareil ne doit pas être raccordé à la terre.

Assurez-vous que l’appareil est correctement aéré. N’empêchez-pas l’air de circuler autour de la plaque d’amplification située à l’arrière. N’obstruez-pas les ouvertures du panneau. N’encastrez-pas cette enceinte dans un rack, une étagère, une niche ou un meuble si le volume disponible à l’arrière ne peut être ventilé par l’air ambiant.

Contrôlez que les câbles ne risquent pas d’être transpercés par les pointes de découplage.

Ne déplacez pas l’appareil en le faisant glisser sur ses pointes. Vous risquez de les arracher ou de créer des dégats.

Prenez simplement garde de ne pas vous piquer.

Introduction

Nous vous remercions d’avoir choisi l’enceinte active de subgrave B&W ASW™2500.

Depuis la création de notre entreprise en 1966, la base invariable de notre philosophie a toujours été la recherche de la perfection absolue.

Inspirée par son fondateur, le regretté John Bowers, cette extraordinaire aventure qu’est la quête de l’absolu, n’a pas seulement débouché sur de très lourds investissements consacrés à la recherche et à l’innovation, mais aussi sur une profonde connaissance de la musique et des spécificités du son cinématographique. Cette

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