In this review, we will be comparing KC92 and ASW608, two Powered Subwoofer speakers from KEF and Bowers Wilkins. Being Powered subwoofers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features of KEF KC92 and B&W ASW608 first before getting into our more detailed comparison.
The sections below take each area in turn: driver and amplifier, frequency response, physical size and connectivity.
Drivers
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.KEF KC92 and B&W ASW608 have a totally different setup: the KEF KC92 features 2 x 9-inch drivers whereas the ASW608 features 1 x 8-inch drivers.
Frequency Response
KC92 has a frequency range of 11-200 Hz whereas ASW608 has a frequency range of 32-140 Hz. With a minimum frequency of 11Hz, the KC92 can go significantly deeper on the low side and provide stronger bass compared to the ASW608's min frequency of 32Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Subwoofer class in our database.
Low Frequency
Subwoofer Speakers
High Frequency
Subwoofer Speakers
Cabinet Type
Both KEF KC92 and B&W ASW608 have Acoustic Suspension type cabinets. Acoustic Suspension aka Sealed type subwoofers have enclosures that are sealed hence no ports or holes exists on the cabinet. Sealed designs helps to provide more accurate and tight bass responses compared to ported designs.
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare KEF KC92's and B&W ASW608's external dimensions. KEF KC92 has external dimensions of 352.5 x 330 x 360.5 mm (13.88 x 13.00 x 14.19 in) whereas B&W ASW608 has external dimensions of 272.0 x 261.0 x 350.0mm (10-11/16 x 10-1/4 x 13-3/4inch).
KEF KC92 is clearly the larger of the two speakers. Its body is 69mm wider, 80mm taller and 11mm deeper than B&W ASW608.
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the KEF KC92 is approximately 1191.3cm2 / 184.7inch2 and base area of the B&W ASW608 is approximately 913.5cm2 / 141.6inch2. The KC92 requires 30% more surface area than the ASW608 which gives it a small disadvantage on placement in tight spaces.
Weight Comparison The weight of a subwoofer may become an important factor if you need to move and reposition the unit often to find the optimal positioning, also known as 'Subwoofer Crawling'. The KEF KC92 weighs 20.00kg / 44lbs and the B&W ASW608 weighs 8.86kg / 19.5lbs. This makes the KC92 126% heavier than the ASW608.
Here is a comparison of how KC92 and ASW608's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of KEF KC92?
Here are the items that are included inside the box of KC92:
- KC92 subwoofer
- Power cord
- Euroblock speaker level connector
- User manual and warranty information
What's in the Box of B&W ASW608?
Here are the items that come with the ASW608:
- Powered subwoofer
- Grille
- 6.5-feet AC power cord
- 4 Rubber feet
- 4 Spike feet
- 4 Lock-nuts
- Manual
- Bowers & Wilkins brochure
- Warranty Information
 Woofer Size |
9 inches
vs
8 inches
|
Larger woofer |
| Number of Woofers |
2
vs
1
|
More woofers |
| Low Frequency Response |
11 Hz
vs
32 Hz
|
Generates deeper bass |
 High Frequency Response |
200 Hz
vs
140 Hz
|
Generates higher frequency |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
 Height |
272mm
vs
352mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
913cm2
vs
1191cm2
|
Takes less floor space |
 Price per pair* |
599USD
vs
1999USD
|
costs less (*prices may change depending on the seller, location and time) |
Size, drawn to scale
Both subwoofers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same floor and pushed back to the same wall, so the bigger one visibly takes more of the room.
KEF KC92 needs about 30% more floor area. KEF KC92 is 80mm taller.
| General |
KEF KC92 |
Bowers & Wilkins ASW608 |
| Brand |
KEF |
Bowers Wilkins |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
1000 watts |
200 watts |
| Frequency Response |
11-200 Hz |
32-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
1000-watt RMS |
200-watt RMS |
Drivers |
|
|
| Woofer Quantity |
2 |
1 |
| Woofer Size |
9" |
8" |
| Woofer Composition |
Polypropylene |
Paper/Aramid Fiber |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
40-140 Hz |
n/a |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
352.0mm (13.9") |
272.0mm (10.7") |
| Width |
330.0mm (13") |
261.0mm (10.3") |
| Depth |
361.0mm (14.2") |
350.0mm (13.8") |
| Weight |
20.00kg (44lbs) |
8.86kg (19.5lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
2 Years |
| Labor Warranty |
2 Years |
2 Years |
Two quite different sizes of subwoofer. Room volume decides this more than anything else on the page: a big driver in a small room is wasted, and a small one in a large room is worked to death.
| Area | Better | Why |
|---|
| Bass depth | A | KEF KC92 goes deeper - 11Hz against 32Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | A | KEF KC92 has the bigger amplifier - 1000W against 200W RMS, about 7dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | KEF KC92 moves more air: 2 x 9" against 8" is 2.53x the cone area, not the 1.59x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | evenly matched | Both are sealed designs, so they roll off in much the same way. |
| Wireless option | depends | Only KEF KC92 offers a wireless link (as a paid option). It decides where the sub can go if you cannot run a cable, and is worth nothing if you can. |
| Cabinet size | depends | B&W ASW608 is about 41% smaller by volume. In a subwoofer that is a real trade rather than a preference: box volume is how you get output low down without a bigger amplifier. |
| Price | B | B&W ASW608 costs less - $599 against $1,999, about 70% less. |
A KEF KC92 B B&W ASW608
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both subwoofers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
The usual trade-off: KEF KC92 measures better, B&W ASW608 costs about 70% less. In a normal room, placement will make a bigger difference than the gap between these two. Two small subwoofers beat one big one in most rooms - a pair evens out the room modes in a way no single box can, whatever its specs. At $599 each, two B&W ASW608 cost about $1,198 against $1,999 for one of the other, which is worth a thought. If placement is the constraint - a corner, behind a sofa, under a desk - B&W ASW608 is the one that will actually go there, and a well-placed small subwoofer beats a badly-placed big one every time.
One thing outweighs everything above: where the subwoofer stands. Room modes can add or remove 10dB or more at a given seat, which is far larger than any difference on this page. Before spending more, try the sub in two or three positions - the crawl test, where you put it in the listening seat and crawl the room to find where the bass sounds best, costs nothing and usually beats an upgrade.