May 2015

Bowers & Wilkins CM10 S2 Floorstanding Loudspeaker
Great sounding speakers that are transparent, sensitive, and easy to drive.
Review By Tom Lyle

 There aren't too many audio brands that cater to audiophiles that manufacture components which can be called crossover products. Of those that are included in this category, the majority are speakers, and where they "crossover" are between high-end customers and the general public. The first of these companies that come to mind is Vandersteen, especially the iterations of their model 2 speakers. Martin-Logan's electrostatic-hybrid speakers can be found in many homes of audiophiles and non-audiophiles alike. Lastly is the British manufacturer that makes the speakers that are featured in this review, Bowers & Wilkins. The name "B&W" can be recognized by just about anyone:  music lovers, audiophiles, and ordinary citizens alike. But of all the speaker brands I mentioned, only B&W can also be found in many recording studios, not just residential abodes.

B&W's CM Series of speakers has served both the manufacture and their customers well. Basically, the CM Series is located in the middle of B&W's lines; the one above it their flagship 800 Series. B&W is hardly one to skimp on quality, but by manufacturing the CM Series in China rather of in the UK as is the 800 Series B&W is able to pass these savings to the costumer without cutting back on quality.  Replacing the CM line is the newer CM S2 line, which builds upon the success of the CM. The five-driver CM10 S2 is at the top of the CM line, and features the striking "Tweeter On Top", a "decoupled double dome" tweeter that is situated on the top of its cabinet.

The CM10 S2 improvements over the earlier CM models include Mundorf EVO capacitors in the crossovers, Van den Hul internal wiring, a nickel-plated terminal tray, and "anti-resonance" dust-plugs for its drivers. The speaker also has a redesigned grille, and one may choose between three finishes on its "extensively braced" "real wood" cabinet. The CM10 S2 has Kevlar fiber/paper drivers, three 6.5" woofers, a 6.5" midrange, and its free-mounted 1" tweeter. The speakers stand over three and half feet tall, over a foot deep, over nine inches wide, and as a benefit the CM10 S2 has a very stable 8 Ohm impedance with a rather high 90dB/W/m sensitivity.

Unpacking and assembling the CM10 S2 was simple and didn't take that long at all. The most demanding step was affixing the plinth. With the provided screws and included Allen wrench it took only a few minutes for each speaker. The speaker cables were connected and I started experimenting with set-up in less than twenty minutes. In regards to their sensitivity I used power amplifiers rated as low as 25 Watts per channel, my Lance Cochrane /Jim Nichols' tube power amp, and as high as 200 Wpc with the Class D Merrill Audio THOR monoblocks (reviewed last month), all with excellent results. Of course the speakers sounded differently with each power amplifier I used, which is testament to the speaker's sonic transparency more than anything else. Which is good. The system in which I reviewed the CM10 S2 is my "second" system in a common space on the first floor of our home. Besides the B&W and EgglestonWorks speakers, and the Merrill and Jim Nichols power amps, I used an LKV Research Line One linestage, a Balanced Audio Technology VK-33 or VK-3iX preamplifier, and at times a rather old Burson PP-160 linestage. The interconnects that run from the linestage or preamplifier to the power amplifier is Cardas, and Cardas cable is also used to connect the power amplifiers to the B&Ws or EgglestonWorks speakers. The digital source is either an Oppo BDP-83 SE (Special Edition) universal player with its analog outputs connected to the linestage or preamplifier using MIT or DH Labs cable interconnect for playing SACDs and the occasional DVD-Audio. Its digital output is connected to either a Benchmark Media DAC1USB, Wadia 121 Decoding Computer or AURALiC VEGA using a MIT or DH Labs digital An alternate digital signal is sourced from my home network using either a discontinued Logitech Squeezebox Touch, but more recently and much better sounding is an AURALiC ARIES wireless streaming bridge (review forthcoming) with its digital output connected to the DAC de jour. All the gear other than the speakers and the Merrill monoblocks rests comfortably upon Metro Commercial shelving.  There is a small area rug in front of the speakers, and the listening seat put my ears just below the level of the tweeters.

Friends
During a recent visit from a couple of audiophile friends we spent some time taking turns seated in the Wassily chair positioned about eight feet away from the center of the speakers. Playing the SACD layer of the reissue of the Chicago Symphony Orchestra's version of Bartok's Concerto For Orchestra conducted by Fritz Reiner proved that the B&W CM10 S2s could hold their own – even when judged by audiophiles who are accustomed to hearing much more elaborate (and much more expensive) speaker systems. One of the first comments was in praise of the CM10 S2's prodigious bass response. This comment is valuable, and more will be said when describing this portion of the CM10 S2's frequency range, but the discussion quickly turned to the speaker's ability to render a very lifelike version of this warhorse. Some might not prefer listening to this version of Concerto For Orchestra because of this rather high level of tape hiss that has remained, despite numerous re-masterings of this recording session. As the production team that was responsible for this reference grade transfer is quick to point out – what is on the tape is on the SACD, so using any sort of noise reduction to lower the level of this somewhat annoying artifact was something they never considered, lest it ruin what is likely to be the last time we're going to hear about a digital transfer of this nearly sixty year old performance. And the amount of tape his that can be heard on this recording relates directly to the comment that was made regarding the lifelike sound of the CM10 S2 – that one gets the sense that one is hearing exactly what is coming from the source upstream. Of course this sound will depend on one's associated equipment, and as I am confident that the quality of the source, the electronics that increased the gain of the source, and the power amplifiers connected to the B&W CM10 S2s are good or better than what is needed to bring out the best in these speakers.

As the SACD of Concerto For Orchestra started, the double basses and cello sections of the orchestra introduce themselves. It was if one could "see" the double bass and cello sections on the right side of the stage. The B&W CM10 S2 is not the largest floor standing speaker on the market, nor does it have huge drivers to handle the low end, yet the sound of these instruments was surprisingly solid, pitch stable, and was remarkably extended. Although the initial shock of the bass response of the CM10 S2 wore off, and I continued to listen to these speakers throughout the audition period they proved that the bass was able to reproduce these frequencies with a satisfyingly realism, regardless of genre.

The reproduction of the mid-range frequencies is what really makes these speakers sound much more expensive than their asking price. When I spun Concerto For Orchestra the string sound was full bodies, never strident, and most importantly realistic sounding. During climatic portions of the score I felt enveloped by the music. The audiophile check-list of attributes were all there – the ability to handle both micro- and macro-dynamic swings, a huge realistically scaled wide and deep soundstage, fantastic imaging, and excellent integration of the drivers. But I would gladly give up any and all of these traits for a palpably realistic sound, one that sounded like music – and these B&Ws delivered. And those who think that an external tweeter might lead to an upper treble that sounds detached from the rest of the speaker can rest easy. It seems that B&W's goal to make a tweeter has excellent imagining and dispersion, and "creates a more lifelike sound and improved sense of space" has been met. There wasn't any time during the audition period, and regardless of which genre or sub-genre that I chose to play through these speakers, when I thought that the treble sounds made themselves blatantly known – the treble was simply there – naturally integrated into the music, and was simply a representation of what was present on the recording.

My last review to appear within Enjoy the Music.com was the Merrill THOR monoblocks in the April 2015 issue. For most of their review period they powered the B&W CM10 S2 and these were excellent speakers to use to  judge this amplifier's traits. Luckily the THOR monoblocks are a very transparent sounding amplifier, and although the CM10 S2 don't require a power amplifier with this much Wattage, using this amount of power was a fine way to assess these speakers' characteristics.

In the review I used a CD of the composer Louis Verne, who wrote many pieces for organ, and when this signal was fed to the CM10 S2 it demonstrated that the bass response of the speakers did not only go much deeper than I had expected (raising the volume shook the floorboards and window frames of the listening room), but the bass was also very pitch stable, and the antitheses of a one-note bass. To test the low-end of the speaker I also spun the DVD-Audio of Genesis' 1972 album Foxtrot, and although the bass of the CM10 S2 doesn't reach into subsonic territory, it easily reaches down into the mid-to-low 30kHz range. This enabled me to revel in Mike Rutherford's Dewtron and Moog Taurus bass pedals, as they are the underpinning of many of the tunes on this classic progressive rock album. The CM10 S2 was able to distinguish not only the pitch of the pedals, but the timbre of the various settings Rutherford would use during different portions of their somewhat long compositions, including their  magnum opus Supper's Ready, which lasts over twenty minutes.

Downloading high-resolution material isn't something I do that often. It took me a while to get used to paying for non-physical music – feeling as if I'm purchasing expensive ether (and getting used to not being able to re-sell what I've bought will obviously take a while, too. Any takers for some lightly used high-resolution FLACs, played only once?). Still, there is no denying the material on HDtracks.com website is awfully tempting, especially after hearing what Lee Morgan's Sidewinder  sounds like with a resolution of 192kHz/24-bit. When playing this album I had a physical reaction to this high-resolution digital file – as the second track, the slightly more than ten minute "Totem Pole" reached the end of the song I rose from my listening seat to change the LP side. But of course there was no LP playing. The CM10 S2 was able to reproduce this recording in a manner that I can only describe as one of the most honest portrayals of music I've heard of what is contained on the master tape. But it was also easy to get lost in the fantastic sounds that were recorded onto this master tape. It's a given that this is one of trumpeter Lee Morgan's best albums, but it is also the album that made me take notice of Joe Henderson. I purchased every Joe Henderson LP and CD I could get my hands on, Mode For Joe is my favorite these days, and I'm lucky enough to be able to listen to the 192kHz/24-bit version I also downloaded from HDTracks. On the Lee Morgan album both his trumpet and Henderson's sax are recorded up close, as most all Rudy Van Gelder albums are wont to be. Both the trumpet and sax do not sound like a trumpet and a sax, they sound like they are a trumpet and a sax, with a reach-out-and-touch palpability. In my listening room it is very rare that an instrument or voice sounds like it is in the same room as me, but when the best equipment visits this room it sounds as if there is a clear window into the recording – as if my mind's ear can see the instruments and voices – and the B&W CM10 S2 did one of the best jobs of performing this feat that I've ever heard from a speaker anywhere near its price.

In fact, it's more than reasonable to assume that because of economies of scale Bowers & Wilkens speakers can offer to its customers a greater level of performance than most other equivalently priced speakers. And many people, non-audiophiles included, expect a certain level of performance from

What sets the CM10 S2 apart from many other speakers near or beyond its price class is its treble. The CM10 S2's externally mounted tweeter not only integrated well with the other drivers, it added a semblance of realism to the sound of all the music that passed through them. The sound of the drumsticks hitting a cymbal, the initial ping, the ring, the ring's decay, and the sound of the air around the cymbal – all contributed to a realism that I've come to expect from a top-flight speaker, yet this speaker is not from B&W's top line of speakers (their 800 Series has that honor) yet this speaker had the refined treble characteristics that I've come to expect from B&W.  Again, when auditioning the Merrill Audio THOR monoblock amps connected to the CM10 S2 pair and when I played my copy of the single-layer Japanese SACD of the Rolling Stone's Beggars Banquet, the treble prowess of the speaker was quite evident. The tape hiss was quite evident, after all, this album was recorded in 1968, but it wasn't very annoying. This hiss was really only evident a split second before the congas and percussion enter on the first track "Sympathy For The Devil". It is a busy recording, with the two extra percussionists, Nicky Hopkins on keys, and two female background vocalists (the beautiful Marianne Faithful and Anita Pallenberg), yet still the CM10 S2 was easily able to unravel it all. This was largely due to not just the detail that the tweeters were able to provide, but the realistic sound that was sent forth into the room, with the huge soundstage behind and to the sides of the speakers. It was a very honest portrayal of what was on the tape. Although it is hardly an audiophile spectacular, it again, simply sounded as if I was hearing what was on the tape – although the rendering of each instrument and voice was uncannily lifelike. And a bit spooky, really, even though I could hear a bit of the artifacts of the recording process – the previously mentioned tape his, a bit of tape overload, and some sounds I couldn't really identify, it still sounded authentic. And like music. And like one of the best rock ‘n' roll songs ever written and recorded. This was regardless of the volume I set the preamplifier as the speakers were able to play extremely loud without the tweeters ever hurting my ears until the sound pressure level was pushed insanely high.

Regards
I had to think for quite a while before I could come up with some negatives regarding the sound quality of these speakers. Sans grilles they may be one of the best looking speakers on the market in their price range, and quite beyond – the combination of the external tweeter, the single yellow Kevlar mid/bass driver above the two other woofers, all with their conical anti-resonance dust caps – no one is likely to mistake these speakers for any other that B&W. I might have preferred a different color than the black I was sent, but that complaint definitely belongs in the nit-picking category, as is easily ignored. Sonically, I thought that perhaps at times the B&W CM10 S2 sounded too good, that material that I knew for a fact was recorded with sub-par sound quality was actually quite listenable through this pair of CM10 S2 speakers. With their high level of transparency, I can only assume that this trait defines the adage "no one sets out to make a bad recording". All engineers, producers, and especially musicians attempt to convey to the listener their musical messages, and whether it falls short of an audiophile's perception of what makes a good sounding recording or not is sometimes not for us to judge. So I'm going to have to give the benefit of the doubt to the CM10 S2 as being able to unravel the meaning behind the music, as well as what's on the tape (or hard-drive... or whatever).

The Bowers & Wilkins CM10 S2 are fine, multi-driver, floorstanding speakers. The sound one gets from them is definitely going to depend on the associated equipment one is using, as well as what room they are placed within. This is not because these speakers are "picky". To the contrary, they sounded great with many different configurations of equipment set-ups that fed them. It is just that they are transparent, sensitive, easy to drive, great sounding speakers, so one will be able to hear what is upstream feeding them. But the listener will be rewarded with being able to hear what the musicians, engineers and producers meant one to hear – the sounds on the recording, and the meaning behind the music. This is because the speakers sound like music. One is going to have to spend much more money on a pair of speakers in able to come close to the quality of sound one is going to get with the B&W CM10 S2. Highly recommended.

Ratings: I tend to rate very conservatively. A five-note rating is reserved for traits of the best state-of-the-art components I've ever heard.

Specifications
Type: Three-way vented-box system
Drivers: 1" decoupled double-dome aluminum high-frequency
            6" woven Kevlar cone FST midrange
            Three 6.5" paper/Kevlar ® cone bass
Frequency Response: 45Hz to 28k Hz (+/-3dB) 
Within 2dB of reference response 
Horizontal: Over 60°
Dispersion: Vertical over 10°
Sensitivity: 90dB/W/m
Harmonic Distortion <0.5% 110Hz-20kHz
Nominal impedance: 8 Ohm (minimum 3.2 Ohm)
Crossover Frequencies: 350Hz and 4kHz
Recommended Amplifier Power: 30 to 300 Watts into 8 Ohm 
Dimensions: 42.8" x 14.4" x 14.3" (HxWxD)
Weight: 73.7 lbs.
Finishes: Rosenut, gloss black, and satin white 
Grille Color: Black or Grey (with satin white finish only)
Price: $3999.99 per pair

Company Information
Bowers & Wilkins (B&W) Group North America
54 Concord Street 
North Reading, MA 01864

Voice: (978) 664 2870
Fax: (978) 664 4109
Website: www.Bowers-Wilkins.com