The new tweeter dome is based in part on the research
conducted on the carbon-braced tweeter used in the B&W PM1 speaker. Here,
the edge of the aluminium dome is strengthened using a second aluminium layer,
creating a new ‘double-dome’ design.

B&W says this approach stiffens the whole structure and
prevents the voice coil from going ‘out of round’ at higher frequencies.

he cabinet height of the CM10 is the same as that of the
CM9 model, but by adding just a little depth to the enclosure and relocating
both the tweeter and FST midrange drive units, there’s sufficient space for an
additional bass drive unit.

What’s more, the CM10’s Kevlar FST driver is decoupled from
the rest of the cabinet to help reduce audible cabinet coloration.

This approach stiffens the whole structure and prevents the
voice coil from going ‘out of round’ at higher frequencies claims Bowers &
Wilkins engineers. The result is the best performance yet from a CM Series
loudspeaker: the double-dome pushes the first break-up frequency up from the
standard dome’s 30 kHz to 38 kHz. This makes the tweeter purer and more
piston-like in the all-important audible band below 20 kHz. The result is
better clarity and control, even under duress.

B&W said that moving the tweeter to the top of the
cabinet has other advantages. The overall cabinet height of CM10 is the same as
that of CM9, but by adding just a little depth to the enclosure and then
relocating both the tweeter and FST midrange drive units creates sufficient
extra volume for an additional bass drive unit. So CM10 has 50 per cent more
bass driver area than CM9, with three drivers rather than two.

It also gains in overall sensitivity, while bass alignment
has been altered, allowing CM10 to be tuned lower. This gives it more
extension, while the extra bass driver also helps reduce distortion, and
enables a higher maximum output level. Attention has also been paid to the
all-important midrange area, and CM10’s Kevlar? FST driver is, for the first
time in the CM Series, decoupled from the rest of the cabinet. This
performance-orientated solution not only reduces audible cabinet coloration,
but also makes the listener less aware of the position of the loudspeaker
itself.

The FST drive unit is secured in place by a drawbar
mechanism, as found in 800 Series Diamond models. Moving the midrange driver
closer to the top of the cabinet has similar results to locating the tweeter on
top: it improves upward dispersion and increases the sense of airiness.

All these improvements combined mean the CM10 can play
louder and go deeper than the CM9, claims B&W. The B&W CM10 will be
available from September in two real-wood finishes, Rosenut or Weng?, or two
painted finishes, Black Gloss or Satin White.

The new speakers will retail in Australia for $5,500 a pair.