The crew here at Sound+Image has been watching for decades, and listening on rare treasured occasions, to Bowers and Wilkins’ 800 Series loudspeakers. We do not hesitate to say that we’ve loved them from the start, but recognise that their costs may put them out of reach for nearly everyone.

But how about one step down? The 700 series. Here we’re looking at a 5.1-channel surround speaker system assembled from models within that 700 series. Or, more precisely, models from the new S2 versions in the 700 Series.

703 S2 with centre and DB4S sub, grilles off

EQUIPMENT
Two models in the series have B&W’s distinctive top-mounted tweeters, but the selections we’re looking at are a little more conventional, with the tweeters mounted in the usual position within the enclosures, even though internally the drivers share the same technology. All employ B&W’s carbon dome tweeters, which have been developed to push the threshold for dome break-up to 47kHz (that’s the point at which the structure of the dome can lose its integrity, increasing distortion significantly). Want high resolution audio? No problem here.

The midrange drivers of the 703 S2 floor-standing front speakers and the HTM71 S2 centre channel are decoupled from the cabinet — physically limiting vibrations from the larger drivers and reducing consequent coloration. These and the bass/midrange drivers of the 706 S2 surround speakers feature B&W’s woven ‘Continuum’ cones derived from the 800 Series Diamond speakers (see the previous review for more details).

The bass drivers of the front three speakers and the subwoofer use B&W’s Aerofoil Profile bass cone, where the material has been designed not just with a standard fold of cone material, but a cone with varying thickness so that it is stronger where needed, lighter elsewhere.

Drivers out - the 703 S2 with grille off

All models in the 700 Series are available in three finishes — satin white, gloss black and a deep Rosenut veneer. We were supplied with a mixture of all three finishes in our review system, but we’ve pictured the full system in white above, and the 703 S2 in Rosenut opposite. With all of them, the construction and finish were immaculate.

All the speakers (bar the subwoofer) are bass reflex loaded with rear ports (smoothly flared with dimpled surfaces like golf balls, the ‘Flowport’ technology B&W introduced something like a dozen years ago). They are supplied with foam bungs so you can further tune the bass according to room location if you need to.

All the speakers should be easy enough loads, with rated impedances of eight ohms and middling sensitivity levels (see the specifications box for details). B&W is unusual in that it often rates the distortion performance of its speakers. The front three speakers are all rated at less than 1% THD for 90dB output (at one metre) for frequencies above 90Hz, and less than 0.5% THD for frequencies above 120Hz. Those thresholds move up to 100Hz and 150Hz for the smaller 706 S2 speakers.

DB4S subwoofer with the 706 S2 as rears

The DB4S subwoofer has specifications which quite belie its compact dimensions: essentially it’s a 37-ish centimetre cube. In the front is the 250mm driver and pushing it is a 1000W Class D Hypex amplifier. A digital preamplifier features DSP and ‘Dynamic EQ’, which allows the subwoofer to tune its capabilities to signal demands and volume levels. (For more on this, see the dedicated subwoofer review which follows.) B&W says that the DB4S subwoofer can reach down to 10Hz at -3dB, and 8.5Hz at -6dB. The unit has both XLR and RCA inputs. There are no rear controls on the unit — instead you adjust settings, including EQ, using an app for iOS or Android.

PERFORMANCE
As is fairly common modern practice, B&W hasn’t engineered the front speakers of this system for ultra deep bass, with the headline ±3dB specification running down to a relatively modest 46Hz (albeit, with 30Hz at -6dB). Why mention this? In a home theatre context you’ll probably want the subwoofer to kick in at 40Hz. That way with stereo music you’ll get all the benefit of these speakers, the sub only doing stuff they can’t do.

But 40Hz is too low a point for the subwoofer to assume duties for the other speakers, especially the surrounds, and doubly especially if you have ceiling-mounted Atmos speakers. So you’ll need to be using a home theatre receiver that allows separate crossover points for ‘small’ speakers. Which is what we used, of course. Indeed, we set this system up with a Yamaha Aventage RX-A3070 receiver and used its two profiles to allow a pure stereo system sans subwoofer, and a surround system with the EQ set to leave the front speakers unadjusted, and the rest set to match.

We started with stereo music and just the 703 S2 floorstanders. And ... wow. Wow. Just wow.
Sometimes with speakers you run through a range of music, listening for what best suits a pair of speakers versus what it isn’t quite so good at. There was none of that here. Everything was simultaneously astonishingly transparent. Sometimes the transparency allowed the source to sound ‘so-so’. But with most content it lifted the sound. A fine modern-ish DSD recording of Cloverfoot Reel with Yo-Yo Ma and friends was delivered on a soundstage that encompassed the entire front of the room, height as well as width, depth as well as height and width.

And this was so-so sweet! Ma’s cello was a thing of true beauty, and it was right there in front of us whenever we closed our eyes.

Yet it isn’t only modern high-res that gets the B&W delivery. The 48-year-old song Spinning Wheel by Blood, Sweat and Tears, accompanied as it was with the tape hiss properly captured by the DSD transfer, was about as exciting as it gets, with its uncompressed dynamics ringing out into the room at whatever volume we chose. We chose big.

Moving back further in time, Herbie Mann’s Watermelon Man seemed to belie those bass
specifications, but it wasn’t so much depth as full and proper delivery of a powerful bass line that was entirely within specification.

DSD is one thing. How about vinyl? We dragged out our LP of the Alan Parsons-produced ‘Year of the Cat’ by Al Stewart, followed by a little Stravinsky ‘Firebird’. Again we were rewarded with astonishing 3D sound from the 703 S2 speakers.

Now for the other speakers to consider. Musically they truly kept up their ends with audio delivery on both DVD-Audio and Blu-ray multichannel music, and in a home theatre context also on the movies we enjoyed with them.

In particular, we watched and listened to Wonder Woman and John Wick: Chapter 2 on Ultra-HD Blu-ray. The system delivered immense volumes of precisely-placed sounds and effects all around the room. Even though we ran without any height speakers, there was still a fine sense of real height in both movies.

As for the subwoofer, we pulled out our ancient copy of Titan A.E. with its opening destruction of our planet and the rather fulsome accompanying infrasonics (which we’ve measured stretching easily to 13Hz). We rotated the volume control clockwise. The result was interesting indeed. We were half expecting the kind of palpable body blow of the best subwoofers, but it was less than hoped for. Then we realised that our listening-room door was open. Closing it and repeating the scene provided a far more satisfying experience — the kind of thing one might enjoy only with a truly massive subwoofer a decade ago. If you want a subwoofer to properly pressurise your room, keep that door closed.

App control of the subwoofer

But there was more to the subwoofer than that. There was also an absence of the irritating harmonic distortion that so often comes with over-driven smaller subs. Because our hearing sensitivity drops so precipitously as the sound descends into deep bass, harmonic distortion can sound tens of decibels higher than it actually measures. And that’s what makes it irritating, oppressive sometimes, with high levels of the third harmonic in particular.

This subwoofer was clean. In parts of that track there’s only the deep bass, and it rumbled away, a super-deep underpinning, completely clear thanks to the lack of distortion.

The subwoofer’s lack of physical controls does not mean an actual lack of controls. They’re in B&W’s DB Subwoofer app (iOS or Android — we used the Android version). This connects to the subwoofer via Bluetooth and allows you choose whether to have ‘auto off’ working, the overall level, the type of connection, a further trim level, and adjustment of the EQ setting. There are some presets for EQ, or you can manually adjust the five bands spread between 20 and 80Hz between -5dB and +5dB.

CONCLUSION
This combination from Bowers and Wilkins’ 700 Series is a serious delight for both stereo and surround music. The system isn’t cheap, but we doubt you’ll get better sound for the money.

Bowers and Wilkins 703 S2 surround speaker system
Total price: $11,296

+ Glorious sound quality
+ Excellent build and finish
+ EQ capability in sub

- No negatives here...

Warranty: Five years (two on subwoofer)

B&W 703 S2: $4699 pair
Drivers: 1 x 25mm dome tweeter,
1 x 150mm midrange, 2 x 165mm bass
Frequency response: 46-28,000Hz ±3dB; -6dB at 30Hz and 33kHz
Impedance: 8 ohms
Sensitivity: 89dB (2.83V@1m)
Power handling: 30-200 watts
(recommended amplifier power)
Cabinet: Bass reflex (rear port)
Dimensions (hwd): 1025 x 200 x 300mm (320 x 370mm incl plinth)
Weight (each): 25kg

B&W HTM71 S2 centre: $1799
Drivers: 1 x 25mm dome tweeter,
1 x 100mm midrange, 2 x 165mm bass
Frequency response: 50-28,000Hz ±3dB; -6dB at 45 Hz and 33kHz
Impedance: 8 ohms
Sensitivity: 89dB (2.83V@1m)
Power handling: 30-100 watts
(recommended amplifier power)
Cabinet: Bass reflex (rear port)
Dimensions (hwd): 225 x 590 x 301mm
Weight: 18.3kg

B&W 706 S2: $2199 pair
Drivers: 1 x 25mm dome tweeter,
1 x 165mm bass
Frequency response: 50-28,000Hz ±3dB; -6dB at 45Hz and 33kHz
Impedance: 8 ohms
Sensitivity: 88dB (2.83V@1m)
Power handling: 30-120 watts
(recommended amplifier power)
Cabinet: Bass reflex (rear port)
Dimensions (hwd): 340 x 200 x 301mm
Weight (each): 8.0kg

B&W DB4S subwoofer: $2599
Driver: 1 x 250mm cone
Frequency response: 10Hz-350Hz -3dB; -6dB at 8.5Hz and 500Hz
Power output: 1000W
Inputs: 2 x RCA, 2 x XLR
Cabinet: Closed
Dimensions (hwd): 377 x 360 x 368mm
Weight: 26kg