In this review, we will be comparing KUBE 8b and SuperCube 4000, two Powered Subwoofer speakers from KEF and Definitive Technology. 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 KUBE 8b and DT SuperCube 4000 first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the KEF KUBE 8b and DT SuperCube 4000 compare and hopefully end up with enough arguments to decide which one of these subwoofers is the better choice for you.
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Drivers
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.KEF KUBE 8band DT SuperCube 4000 have the same driver set up: Both subwoofers have 1 x 8" drivers.
Frequency Response
KUBE 8b has a frequency range of 34-140 Hz whereas SuperCube 4000 has a frequency range of 16-200 Hz. With a minimum frequency of 16Hz, the SuperCube 4000 can go significantly deeper on the low side and provide stronger bass compared to the KUBE 8b's min frequency of 34Hz.
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
The KEF KUBE 8b has a Acoustic Suspension type cabinet. 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. On the other hand the DT SuperCube 4000 have Passive Radiator type enclosure. Passive Radiator type subwoofers sports a non-powered cone that moves in response to the main woofer to move air out in order to generate stronger bass in a smaller body compared to ported or sealed designs.
Physical Specs
Size of a speaker can sometimes become 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 KUBE 8b's and DT SuperCube 4000's external dimensions. KEF KUBE 8b has external dimensions of 294.0 x 296.0 x 339.0mm ( 11-9/16 x 11-5/8 x 13-5/16inch) whereas DT SuperCube 4000 has external dimensions of 302.0 x 281.0 x 318.0mm ( 11-7/8 x 11-1/16 x 12-1/2inch) .
DT SuperCube 4000 is 15mm narrower and 21mm less deeper than KEF KUBE 8b but it is also 8mm taller.
Below you can see the front view size comparison of KEF KUBE 8b and DT SuperCube 4000 in scale.
Comparison image of KEF KUBE 8b and DT SuperCube 4000 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 KEF KUBE 8b is approximately 1003.4cm2 / 155.5inch2 and base area of the DT SuperCube 4000 is approximately 893.6cm2 / 138.5inch2. The KUBE 8b requires 12% more surface area than the SuperCube 4000 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 KUBE 8b weighs 11.36kg / 25lbs and the DT SuperCube 4000 weighs 11.36kg / 25lbs.
Here is a comparison of how KUBE 8b and SuperCube 4000'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 KUBE 8b?
Here are the items that are included inside the box of KUBE 8b:
Powered subwoofer6.5-feet AC power cordSpeaker-level input blockUser ManualImportant Safety InformationWarranty Information
What's in the Box of DT SuperCube 4000?
Here are the items that come with the SuperCube 4000:
8-inch Powered subwoofer7-feet AC power cordRemote control (CR2025 battery installed)4 Threaded rubber-feet4 Spike feet (hex-nut attached)Owners ManualSC4000 Booklet
 Height |
294mm
vs
302mm
|
Easier to fit in smaller spaces |
 Low Frequency Response |
16 Hz
vs
34 Hz
|
Generates deeper bass |
 High Frequency Response |
200k Hz
vs
140k Hz
|
Generates higher frequency |
 Base Surface Area |
893cm2 (281x318mm)
vs
1003cm2 (296x339mm)
|
Takes less floor space |
| General |
KEF KUBE 8b |
Definitive Technology SuperCube 4000 |
| Brand |
KEF |
Definitive Technology |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
1200 watts |
| Frequency Response |
34-140 Hz |
16-200 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
1200-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
8" |
| Woofer Composition |
Not given |
Not given |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
40-140 Hz |
40-150 Hz and 40-150 Hz |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
294.0mm (11.6") |
302.0mm (11.9") |
| Width |
296.0mm (11.7") |
281.0mm (11.1") |
| Depth |
339.0mm (13.3") |
318.0mm (12.5") |
| Weight |
11.36kg (25lbs) |
11.36kg (25lbs) |
| Enclosure |
Acoustic Suspension |
Passive Radiator |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
3 Years |
| Labor Warranty |
2 Years |
3 Years |