Bowers & Wilkins 800, 802 manual Connecting, English, Important Safety Notice

4. Connecting

ENGLISH

All connections should be made with the audio equipment switched off.

The 800 Diamond and 802 Diamond speaker terminals accept a variety of cable terminations: 4mm banana plugs, 6mm and 8mm (1/4 in and 5/16 in) spades, or bare wires up to 4mm (5/32 in) diameter.

Important Safety Notice

In certain countries, notably those in Europe, the use of 4mm banana plugs is considered

a potential safety hazard, because they may be inserted into the holes of unshuttered mains supply sockets. In order to comply with European CENELEC safety regulations, the 4mm holes in the ends of the terminals are blocked by plastic pins. If you are using the products in any country where these conditions apply, you should ensure that any banana plugs cannot be used in an unsafe manner by children or other uninformed persons.

Ask your dealer for advice when selecting speaker cable. Keep its total impedance below the maximum recommended in the speaker specification and use a low inductance cable to avoid attenuation of high frequencies.

There are two pairs of terminals at the back of each speaker that enable bi-wiring (left). For conventional, single wire connection, fit the supplied link wires to join the like polarity terminals together (right). If the cable from the amplifier has spade connectors, fit the link wires using the 4mm hole at the end of each terminal. If it has banana plugs, fit the link wires into the cross holes. You may also need to remove the caps of the two terminals used for the cable from the amplifier in order to maximise contact area, especially if its banana plugs are short.

Ensure that the positive terminals on the speaker (red) are connected to the positive output terminal on the amplifier and the negative terminals on the speaker (black) are always connected to the negative output terminal on the amplifier. Incorrect connection will not result in damage but will cause poor stereo imaging and loss of bass. Always screw the terminal caps down fully to prevent rattles.

Note: Bi-wiring separates the signal paths to each section of the speaker and can improve both stereo imaging and detail resolution. It also enables the use of different types of cable for each frequency band.

Bi-amplification goes a stage further and involves the use of two independent power amplifier channels for each speaker. This is not the same as a fully “active” drive as the speaker's internal passive crossover is still used. If bi-amplification is employed, ensure that each amplifier channel has the same gain, otherwise the speaker’s tonal balance will be distorted.

Check also the absolute polarity of the amplifiers. Some amplifiers invert the signal, and their use in combination with non-inverting types will result in a distorted frequency response. If you have a mixture of inverting and non-inverting amplifiers, reverse the polarity of the speaker connections from the inverting amplifier.

Bear in mind that, even though midrange and, even more so, tweeter drivers can (and only need to) handle less continuous power than bass drivers, the amplifier feeding them needs to have an adequate voltage swing in order to supply the short-term high-frequency peaks in music without distortion. A high voltage capability implies high power, so it is not particularly desirable to have a lower powered amplifier feeding the midrange and tweeter than is used for bass drivers.

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