Limited Warranty, Running-in Period | Bowers & Wilkins CM5 instruction

Moving the speakers further from the walls will generally reduce the volume of bass. Space behind the speakers will also help to create an aural impression of depth. Conversely, moving the speakers closer to the walls will increase the volume of bass. If you want to reduce the volume of bass without moving the speakers further from the wall, fit the foam plugs or, for less severe bass reduction, the foam rings in the port tubes. Fitting a foam plug or ring in a port tube is illustrated in Figure 3.

If the bass seems uneven with frequency this will most probably be due to resonance modes in the listening room. Even small changes in the position of the speakers or the listening position can have a profound effect on how these resonances affect the sound. Try moving the listening position or locating the speakers along a different wall. The presence and position of large pieces of furniture can also influence resonance modes.

If the central image lacks focus, try moving the speakers closer together or angling them inward so that they point at a location just in front of the listening position. Figure 1b illustrates speakers angled inwards.

If the sound is too bright, increasing the amount of soft furnishing in the room (heavier curtains for example) may help balance the sound. Conversely, reducing the amount of soft furnishing may help brighten a dull sound.

Some rooms suffer from “flutter echoes” – echoes that “bounce” between parallel room boundaries. Flutter echoes can colour the sound of the speakers in the room. Test for flutter echoes by standing in the middle of the room and clapping your hands. Flutter echoes can be reduced by placing irregular shaped items or non-reflective surfaces, bookshelves, rugs or pictures for example, on one of the offending walls or floor.

Ensure that the speaker stands are upright and firm on the floor. Use carpet piercing spikes if appropriate and adjust them to take up any unevenness.

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.

However, longer run-in periods (as long as a month) have been reported and there is evidence to suggest that this has little to do with the speaker changing and more to do with the listener getting used to the new sound. This is especially so with highly revealing speakers such as these where there may be a significant increase in the amount of detail compared with what the listener has previously been used to; the

sound may at first appear too “up front” and perhaps a little hard. After an extended period of time the sound will seem to mellow, but without losing clarity and detail.

Aftercare

The cabinet surfaces usually only require dusting. If you wish to use an aerosol or other cleaner, remove the grille first by gently pulling it away from the cabinet. Spray aerosols onto the cleaning cloth, not directly onto the product. Test a small area first, as some cleaning products may damage some of the surfaces. Avoid products that are abrasive, or contain acid, alkali or anti-bacterial agents. Do not use cleaning agents on the drive units. The grille fabric may be cleaned with a normal clothes brush whilst the grille is detached from the cabinet. Avoid touching the drive units, especially the tweeter, as damage may result.

In order to avoid the risk of the surface finish cracking, keep the product away from sources of direct heat such as radiators and warm air vents. Whenever Bowers & Wilkins speakers are finished in real wood, the finest veneers are selected and treated with an ultra-violet resistant lacquer to minimise changes in colour over time. Nevertheless, like all natural materials, the veneer will respond to its environment and a degree of colour change is to be expected. The effect may be particularly noticeable where the area covered by the grille, or areas kept in shadow, change more slowly than other areas. Colour differences may be rectified by exposing all the veneer surfaces equally and evenly to sunlight until the colour is uniform. This process can take several days or even weeks, but may be accelerated by careful use of an ultra-violet lamp.

Limited Warranty

This product has been designed and manufactured to the highest quality standards. However, if something does go wrong with this product, B&W Group Ltd. and its national distributors warrant free of charge labour (exclusion may apply) and replacement parts in any country served by an official B&W distributor.

This limited warranty is valid for a period of five years from the date of purchase or two years for electronics including amplified loudspeakers.

Terms and Conditions

1The warranty is limited to the repair of the equipment. Neither transportation, nor any other costs, nor any risk for removal, transportation and installation of products is covered by this warranty.

2This warranty is only valid for the original owner. It is not transferable.

3This warranty will not be applicable in cases other than defects in materials and/or workmanship at the time of purchase and will not be applicable: