In this review, we will be comparing SB-4000 and KF92, two Powered Subwoofer speakers from SVS and KEF. 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 SVS SB-4000 and KEF KF92 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.SVS SB-4000 and KEF KF92 have a totally different setup: the SVS SB-4000 features 1 x 13.5-inch drivers whereas the KF92 features 2 x 9-inch drivers.
Frequency Response
SB-4000 has a frequency range of 19-310 Hz whereas KF92 has a frequency range of 11-200 Hz. With a minimum frequency of 11Hz, the KF92 can go significantly deeper on the low side and provide stronger bass compared to the SB-4000's min frequency of 19Hz.
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 SVS SB-4000 and KEF KF92 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 SVS SB-4000's and KEF KF92's external dimensions. SVS SB-4000 has external dimensions of 466.0 x 453.0 x 532.0mm (18-5/16 x 17-13/16 x 20-15/16inch) whereas KEF KF92 has external dimensions of 353.0 x 331.0 x 362.0mm (13-7/8 x 13 x 14-1/4inch).
SVS SB-4000 is clearly the larger of the two speakers. Its body is 122mm wider, 113mm taller and 170mm deeper than KEF KF92.
Below you can see the front view size comparison of SVS SB-4000 and KEF KF92 in scale.
Comparison image of SVS SB-4000 and KEF KF92 Size and External Dimensions
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 SVS SB-4000 is approximately 2410.0cm2 / 373.6inch2 and base area of the KEF KF92 is approximately 1198.2cm2 / 185.7inch2. The SB-4000 requires 101% more surface area than the KF92 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 SVS SB-4000 weighs 46.50kg / 102.3lbs and the KEF KF92 weighs 20.05kg / 44.1lbs. This makes the SB-4000 132% heavier than the KF92.
Here is a comparison of how SB-4000 and KF92's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of SVS SB-4000?
Here are the items that are included inside the box of SB-4000:
- Powered subwoofer
- Grille
- 6-feet AC power cord
- Remote control
- 4 Elastomer feet
- Owners Manual
- Important Safety Instructions
What's in the Box of KEF KF92?
Here are the items that come with the KF92:
- Powered subwoofer
- 6.5-feet AC power cord
- Speaker-level input block
- User Manual
- Important Safety Information
- Warranty Information
 Woofer Size |
13.5 inches
vs
9 inches
|
Larger woofer |
 High Frequency Response |
310 Hz
vs
200 Hz
|
Generates higher frequency |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
 Price per pair* |
1800USD
vs
2000USD
|
costs less (*prices may change depending on the seller, location and time) |
| Number of Woofers |
2
vs
1
|
More woofers |
| Low Frequency Response |
11 Hz
vs
19 Hz
|
Generates deeper bass |
 Height |
353mm
vs
466mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1198cm2
vs
2410cm2
|
Takes less floor space |
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.
SVS SB-4000 needs about 101% more floor area. SVS SB-4000 stands 170mm further into the room. SVS SB-4000 is 113mm taller.
| General |
SVS SB-4000 |
KEF KF92 |
| Brand |
SVS |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
1200 watts |
1000 watts |
| Frequency Response |
19-310 Hz |
11-200 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
1200-watt RMS |
1000-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
2 |
| Woofer Size |
13.5" |
9" |
| Woofer Composition |
Composite/Glass Fiber |
Hybrid aluminum |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
n/a |
Physical Specs |
|
|
| Height |
466.0mm (18.3") |
353.0mm (13.9") |
| Width |
453.0mm (17.8") |
331.0mm (13") |
| Depth |
532.0mm (20.9") |
362.0mm (14.3") |
| Weight |
46.50kg (102.3lbs) |
20.05kg (44.1lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
5 Years |
2 Years |
| Labor Warranty |
5 Years |
2 Years |
No single best subwoofer here. Your room, where the box can physically go, and whether this is mainly for films or mainly for music will settle it long before the specs do.
| Area | Better | Why |
|---|
| Bass depth | B | KEF KF92 goes deeper - 11Hz against 19Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | evenly matched | Much the same amplifier (1200W vs 1000W RMS) - under 1dB apart. |
| Driver area | evenly matched | Near-identical radiating area (13.5" against 2 x 9"). |
| Enclosure | evenly matched | Both are sealed designs, so they roll off in much the same way. |
| Speaker-level inputs | B | 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 62% 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. |
| Warranty | A | SVS SB-4000 carries 5 years on parts against 2 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | A | SVS SB-4000 costs less - $1,800 against $2,000, about 10% less. |
A SVS SB-4000 B KEF KF92
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 KF92 measures better, SVS SB-4000 costs about 10% less. In a normal room, placement will make a bigger difference than the gap between these two. 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. If placement is the constraint - a corner, behind a sofa, under a desk - KEF KF92 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.