[This review originally appeared in issue 65 of Hi-Fi Plus magazine, which is published in the U.K.]
The 600 Series has been a constant stream of musical pleasure for entry-level and cash-strapped audio enthusiasts for the longest time. The latest iteration builds on this, but with a twist to two. Like the Krell S300i on pages 48-50 in this issue, the new 600 range – two standmounts, two floorstanders and a subwoofer – features local design and global production. The 684 floorstander tested here is typical; it is designed in the Steyning plant in West Sussex and built in China.
Curiously, the nomenclature is back to front. Normally, the higher the number, the better the speaker, but the top model in the 600 range is the 685, and below this model are the 685 standmount and the entry-level 686. It’s nothing to get concerned about of course, but might cause confusion when trawling through the price comparison sites.
The 684 is a ported, two-and-a-half-way design. It’s sporting the now standard B&W issue Flowport golfball-pitted port both fore and aft, a 25mm aluminium dome tweeter and a pair of 165mm Kevlar mid-bass units with hard ‘bullet’ phase plugs in the acoustic centre of each driver.
Each speaker comes supplied with a pair of ‘flexibungs’ (I’ve got all her movies); these allow the speaker to be extremely fine tuned to its environment, as you can have the front bung in, the rear bung out, in, out, in/out and the middle of the bung out. In total, this gives you nine different acoustic modifications to the same loudspeaker and that gives you a lot of freedom in positioning and room size. That being said, the best placement is in a medium sized room (5x4m or larger), firing down the longest axis and approximately half a metre from the rear and side walls. I found that after a lot of experimentation, the best sound came from using the outer portion of the bungs in both speakers, but the dynamics of my room meant it worked well (arguably better) with left bung being complete and the right being just the doughnut, not the whole bung, with a mild toe-in.
My only gripe here concerns the manual, which makes little useful mention of how to use the flexibungs and many will just give up because of this. It’s worth the effort and experimentation, because the loudspeaker benefits greatly from trying out all the different options. So, here’s what the manual should say on this – The two ports are tuned to slightly different frequencies with and without ports; the rear port can be used to subtly tailor the way the loudspeaker interacts with the room. If you have to place the speakers closer to the rear wall than the recommended half metre, try inserting the bungs into the rear ports (first the round outer section of the bung, then the bung entirely). Don’t make snap decisions. The front port tailors the bass output for the room; once you have positioned the speaker properly, experiment with the front bungs in order to accurately match the bass to the rest of the performance. Once again, don’t jump to any snap decisions.
Initially, Bowers and Wilkins supplied the 684 with just the spikes, and initial findings surrounding the speaker (‘best played loud’) reflected possible issues with centre of gravity. Pretty soon after, the 684 shipped with a black plinth with a set of spacers to raise the speaker a centimetre or so off the baseplate, house spikes and widen the footprint. That, plus the slight increase in mass at the base of the speaker, does help give the 684 a sturdy footing. The company includes both spikes and little white rubber feat for those mounting on bare floors. Purists might think anything other than spikes is an abomination, but this is a practical solution that – in practice – works better on a hard wood floor than spikes in this context.
The finish is very slick, although irrespective of whether you use the grilles or not, you are faced with a big slab of flat black to the front and the plinth. The rear and sides are finished in several vinyl woodprint wraps, including light oak, cherry, wengé and black ash. Personally, I think the speakers look better with grilles off, highlighting that distinctive off-centre Bowers & Wilkins tweeter surround logo. I also think the speakers benefit from grille removal where possible; although supposedly acoustically transparent, I’m not entirely convinced and felt the speaker lost a bit of mid and top clarity with the grilles in place. The bi-wire rear panel is usefully set low, so speaker cables rise only a few inches up the back of the speaker itself.
These are deceptively heavy loudspeakers (thanks in part to the B&W trait of a healthy amount of internal bracing) and the plinths mean they top 18kg. And they are efficient and easy to drive too; 90dB sensitivity, with an eight ohm impedance (although the company also claims a three-ohm minimum impedance).
The 684 makes a typical Bowers and Wilkins sound, with a twist or two; very clean, extremely neutral and very, very competent. Exciting too, the combination of taut, surprisingly deep bass and bright treble makes for a speaker with a zing to them. Twist number one: perhaps a little too much zing for some. It’s not a rising treble, nor is it a treble with a definite peak or sting, but the 684 seems to make the top end of a piano sound more like a piano than a real piano.
For most, though, this will just make the speakers sound exciting and alive. Playing Lambchop’s Is A Woman album through the 684 showed just how minor this treble lift is; the sound is very open and Kurt Wagner’s speak-sing vocals come across brilliantly, thanks to a very open and clean midrange. The top remains untouched, except for a very slight increase in the guitar vibrato effect. This is a subtle effect on a relatively obscure background part of the mix.
Bass is exceptionally good, and not just ‘for the money’. Once the experiment process with bungs and placement is over, bass is both deep and taut, and that easy drive means it will be like that irrespective of the amplifier used. And this is one of the most important plus points for the 684 – it’s remarkably unfussy as to its business partners. It will deliver a remarkably similar performance whether it’s the most expensive part of the signal chain, or the cheapest. Differences are still apparent, but not as marked as many designs. And yet, this doesn’t come at the expense of the musical presentation. It’s a remarkable leveller of equipment,. I suspect that might disenfranchise those who want the sound of their expensive CD and amps to be immediately apparent, but for many others this is a handy bonus. Arcam, Cambridge Audio, Marantz, NAD and (obviously, given the company connections) Rotel would be logical choices for electronics happiness.
The 600 Series speakers have often had exciting treble and deeper than you might expect bass for any given cabinet size. The problem in the past has been a sound that had ‘all top, all bottom… nothing in between’. Worse, as you went up the 600 Series, so the gap between bass and treble widened. Fortunately, based on the evidence of the 684 at least, those days are gone and one of the best parts of this loudspeaker is its clean, open midrange. There are so many recordings that demand a good midrange, but All Is Yes by The Blessing really takes advantage of this. The percussive piano and drum kit, coupled with a Miles-esque muted trumpet can all so easily degrade into a midrange-free zone, but the 684 brings out the less accented bit in the middle.
Stereo is fine, although those looking for a pair of speakers that throw out a huge soundstage or a lot of image depth will be disappointed. Increasing toe-in improves stereo imaging considerably, but does so by trading precision in the bass. It’s a question of balance.
In fact, balance is the key to the Bowers & Wilkins 684. There are speakers that might do one or two things better (superior imaging, for example), but at the expense of other aspects (overall balance, detail, compatibility, fun). These will prove perhaps more attractive to people seeking the same. However, the 684 should be considered the default choice for £700 loudspeakers. It’s the benchmark at the price.
Bowers and Wilkins 684 floorstanding loudspeaker
Type: Two-and-a-half way reflex loaded floorstanding loudspeaker
Driver Complement: 1x 25mm aluminium dome tweeter, 1x 165mm woven Kevlar® cone bass/midrange, 1x 165mm woven Kevlar® cone bass
Bandwidth: 44Hz–22kHz ±3dB on reference axis, -6dB at 34Hz and 50kHz
Sensitivity: 90dB (2.83V, 1m)
Impedance: 8 ohms nominal (minimum 3 ohms)
Dimensions (WxHxD, not including plinth or feet): 198 x 910 x 300mm
Finishes: Black Ash Vinyl, Light Oak Vinyl (not available in US/Canada), Red Cherry Vinyl, Wengé Vinyl
Manufacturer: BW Group Ltd
Tel: +44 (0) 1903 221 500