In this review, we will be comparing KF92 and DB4S, 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 KF92 and B&W DB4S 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 KF92 and B&W DB4S have a totally different setup: the KEF KF92 features 2 x 9-inch drivers whereas the DB4S features 1 x 10-inch drivers.
Frequency Response
KF92 has a frequency range of 11-200 Hz whereas DB4S has a frequency range of 10-350 Hz. With a minimum frequency of 10Hz, the DB4S can go slightly deeper then the KF92's min frequency of 11Hz.
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 KF92 and B&W DB4S 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 KF92's and B&W DB4S's external dimensions. KEF KF92 has external dimensions of 353.0 x 331.0 x 362.0mm (13-7/8 x 13 x 14-1/4inch) whereas B&W DB4S has external dimensions of 375.0 x 362.0 x 434.0mm (14-3/4 x 14-1/4 x 17-1/16inch).
B&W DB4S is clearly the larger of the two speakers. Its body is 31mm wider, 22mm taller and 72mm deeper than KEF KF92.
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 KF92 is approximately 1198.2cm2 / 185.7inch2 and base area of the B&W DB4S is approximately 1571.1cm2 / 243.5inch2. The KF92 requires 24% less surface area than the DB4S which gives it a small advantage 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 KF92 weighs 20.05kg / 44.1lbs and the B&W DB4S weighs 26.05kg / 57.3lbs. This makes the DB4S 30% heavier than the KF92.
Here is a comparison of how KF92 and DB4S'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 KF92?
Here are the items that are included inside the box of KF92:
- Powered subwoofer
- 6.5-feet AC power cord
- Speaker-level input block
- User Manual
- Important Safety Information
- Warranty Information
What's in the Box of B&W DB4S?
Here are the items that come with the DB4S:
- Powered subwoofer
- Grille
- 6.5-feet AC power cord
- 4 Decoupling feet
- 4 Rubber feet
- 4 Spike feet
- 4 Lock-nuts
- Cleaning cloth
- Quickstart Guide
- Bowers & Wilkins brochure
- Warranty Information
- Cleaning cloth instructions
 Number of Woofers |
2
vs
1
|
More woofers |
 Height |
353mm
vs
375mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1198cm2
vs
1571cm2
|
Takes less floor space |
 Price per pair* |
2000USD
vs
2199USD
|
costs less (*prices may change depending on the seller, location and time) |
| Woofer Size |
10 inches
vs
9 inches
|
Larger woofer |
| Low Frequency Response |
10 Hz
vs
11 Hz
|
Generates deeper bass |
 High Frequency Response |
350 Hz
vs
200 Hz
|
Generates higher frequency |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
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.
B&W DB4S needs about 31% more floor area. B&W DB4S stands 72mm further into the room. B&W DB4S is 22mm taller.
| General |
KEF KF92 |
Bowers & Wilkins DB4S |
| Brand |
KEF |
Bowers Wilkins |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
1000 watts |
1000 watts |
| Frequency Response |
11-200 Hz |
10-350 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
1000-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
2 |
1 |
| Woofer Size |
9" |
10" |
| Woofer Composition |
Hybrid aluminum |
Aerofoil |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
353.0mm (13.9") |
375.0mm (14.8") |
| Width |
331.0mm (13") |
362.0mm (14.3") |
| Depth |
362.0mm (14.3") |
434.0mm (17.1") |
| Weight |
20.05kg (44.1lbs) |
26.05kg (57.3lbs) |
| 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 | evenly matched | Effectively the same reach (11Hz vs 10Hz). |
| Amplifier power | evenly matched | Much the same amplifier (1000W vs 1000W RMS) - under 1dB apart. |
| Driver area | A | KEF KF92 moves more air: 2 x 9" against 10" is 1.62x the cone area, not the 1.27x 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. |
| Speaker-level inputs | A | KEF KF92 takes a speaker-level connection as well as line level. That is what lets it work with an integrated amplifier or a vintage receiver that has no subwoofer output at all. |
| Cabinet size | depends | KEF KF92 is about 28% 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 | A | KEF KF92 costs less - $2,000 against $2,199, about 9% less. |
A KEF KF92 B B&W DB4S
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?
KEF KF92 has the edge on paper, though not by much. The "depends" rows are more likely to decide this than the score is. Check your amplifier first: if it has no subwoofer or preamp output, KEF KF92 is the only one of these two you can connect at all.
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.