Tweeter on Top
Although the CM10 is a three-way speaker like the CM9, it has an extra bass driver (diameter = 150 mm) and is taller on the whole. And, as you can see, B&W has put the tweeter on top of the CM10, promising to improve "imaging and dispersion for a more natural, spacious sound". This also makes room to rearrange and lower the speakers in the main part of the cabinet. The cabinet itself has actually been trimmed in height by 9 cm (to 90 cm). Add to that the 6 cm tweeter, and the CM10 is 108.7 cm tall with its "plinth" stand but without the additional feet. Depth-wise, the CM10 has gained 3 cm, notably due to the mid-range speaker and its mounting system (more on that later) and it weighs in at 33.5 kg, which is 7 kg heavier than the CM9. The base has therefore been made a little bigger to improve stability.
Even if the tweeter is now stuck out on top, the CM10 definitely have the general look of CM-series speakers. The finish is absolutely flawless. Plenty of competitors would do well to follow B&W's lead with this level of attention to detail with the build, assembly and finish. Whether you choose one of the wood finishes (wenge or rosewood) or the glossy black version, the CM10 is just impeccable. It's sturdy and feels perfectly well assembled. Plus, the new plinth-style base makes a stylish and practical addition.
The twin terminals around the back are built sleekly into the cabinet and are compatible with banana plugs. Plus, the magnetic grille attachments on the front keep the speakers free from any visible screws or points of attachment. And that's especially good since CM speakers are often left with no grilles.
Finally, the mid-range speaker and tweeter are decoupled from their casing using shock-absorbing gel. The mid-range driver just needs to be quickly unscrewed after delivery to free it up. Seeing as the tweeter is sitting up on top of the cabinet, it becomes ever-so-slightly mobile once all the packaging has been removed. However, you'll need to keep roving hands and curious kids well away from the tweeters. They're no doubt easily replaceable, but given the initial price of the CM10, it definitely pays to be careful.
King of the CM Series
While many of this speaker's features—from design to build to audio specs—place it well and truly in the CM series, it's actually something of a hybrid model, borrowing technology from the top-end 800 series. Bowers & Wilkins has also drawn on its Nautilus and PM1 models when building the CM10.
Frequency response for the B&W CM10 (x axis = low > high frequencies)
When it comes to bass and low frequencies, the technology may not be revolutionary, but it works. Apart from a deeper cabinet, the main modification here is the addition of a third bass driver that boosts the frequency response. The difference is immediately audible. But beyond gaining a few Hertz, the CM10 also delivers bass that's more sustained, more responsive and more straight down the line than with the CM9. It can even be quite surprising at times. With big, full, rich sounds, you could for a split second be tricked into thinking that the CM10 isn't quite on par with the CM9, but that's not the case. The curt, short impacts and the loss of the slight hum—that low but audible level of distortion in the CM9—can just be a little misleading for the first few seconds. All in all, B&W has made good progress here, taking the CM10 a step up from the CM9.
Mid-range frequencies are covered by a woven Kevlar FST speaker. This time it's a little different to what's been seen in the CM9. The speaker enclosure is decoupled from the casing and is held in place around the back by a long screw. There are therefore no screws or nuts visible on the front face of the speaker. A disc of shock-absorbing gel is then positioned just behind the speaker and in front of the screw to improve decoupling.
Here too, the progress made by B&W is immediately audible. Voices in particular feel more present and more natural. When tested side by side, the CM9 seems to have a slight megaphone effect ... which just goes to show how impressive the CM10 actually is.
The real revolution compared with other CM speakers is the new tweeter. As well as being moved up on top of the cabinet and being treated to a dose of insulating gel, its internal design has been derived from tweeters seen in B&W's pricier, top-of-the-range speakers. The B&W Nautilus uses tweeters with an aluminium dome with an inner carbon ring, making the build sturdy but not heavy. These carbon-braced tweeters sound great on paper, but they can be tricky to make and use in practice. The PM1 saw the carbon ring move to the front of the dome in a new and successful take on this design. And the CM10 tweeter is built on the same basic principle, although carbon has been has been replaced with aluminium to keep costs down. However, this new aluminium-dome tweeter still uses a Nautilus tube.
Both our test results and our ears confirmed that the change in structure and the decoupled design have a definite effect on output. High frequencies are clearer and more precise, but they also sound more open. The angle of dispersion for high frequencies is much wider. It's so striking that even untrained ears can hear the difference.
All in all, the Bowers & Wilkins CM10 is a big-hitter in the audio world. It outclasses the CM9 in every respect. The CM10 inherits the main characteristics of the CM series, with an output that has plenty of energy—without being aggressive—while also bringing improved dynamic range and clarity. It's quite brilliant with rock or electro music, perfectly pleasant with classical music and fantastic with jazz. In fact, the various improvements made to this model make it even more versatile than the CM9.
Obviously, after hearing this kind of quality in action, it's difficult to settle for anything lower down the B&W range. Even if the CM8 and CM9 both still offer very good performances, upgrading to the CM10 will be very tempting indeed, even if you've already shelled out for lower-end models. Too bad for your bank balance, as the CM10 are scheduled to sell for £3,000 a pair.