In this review, we will be comparing Kube 15 MIE and SuperSub X, two Powered Subwoofer speakers from KEF and GoldenEar. 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 15 MIE and GoldenEar SuperSub X 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.
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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 15 MIE and GoldenEar SuperSub X have a totally different setup: the KEF Kube 15 MIE features 1 x 15-inch drivers whereas the SuperSub X features 2 x 8-inch drivers.
Frequency Response
Kube 15 MIE has a frequency range of 20-140 Hz whereas SuperSub X has a frequency range of 12-250 Hz. With a minimum frequency of 12Hz, the SuperSub X can go significantly deeper on the low side and provide stronger bass compared to the Kube 15 MIE's min frequency of 20Hz.
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 15 MIE 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 GoldenEar SuperSub X 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
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 Kube 15 MIE's and GoldenEar SuperSub X's external dimensions. KEF Kube 15 MIE has external dimensions of 519 x 500 x 515 mm (20.4 x 19.7 x 20.3 in) whereas GoldenEar SuperSub X has external dimensions of 324.0 x 356.0 x 388.0mm (12-3/4inch x 14inch x 15-1/4inch).
KEF Kube 15 MIE is clearly the larger of the two speakers. Its body is 144mm wider, 195mm taller and 127mm deeper than GoldenEar SuperSub X.
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 15 MIE is approximately 2575.0cm2 / 399.1inch2 and base area of the GoldenEar SuperSub X is approximately 1381.3cm2 / 214.1inch2. The Kube 15 MIE requires 86% more surface area than the SuperSub X 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 15 MIE weighs 27.50kg / 60.5lbs and the GoldenEar SuperSub X weighs 18.18kg / 40lbs. This makes the Kube 15 MIE 51% heavier than the SuperSub X.
Here is a comparison of how Kube 15 MIE and SuperSub X'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 15 MIE?
Here are the items that are included inside the box of Kube 15 MIE:
- Kube 15 MIE subwoofer
- Power cord
- Euroblock speaker level connector
- User manual and warranty information
What's in the Box of GoldenEar SuperSub X?
Here are the items that come with the SuperSub X:
- Powered Subwoofer
- 10-feet AC power cord
- Owners Manual
 Woofer Size |
15 inches
vs
8 inches
|
Larger woofer |
 Price per pair* |
1399USD
vs
1499USD
|
costs less (*prices may change depending on the seller, location and time) |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
| Number of Woofers |
2
vs
1
|
More woofers |
| Low Frequency Response |
12 Hz
vs
20 Hz
|
Generates deeper bass |
 High Frequency Response |
250k Hz
vs
140k Hz
|
Generates higher frequency |
 Passive Radiator |
two 10.5-inch x 9.5-inch
vs
None
|
Increases the bass performance |
 Height |
324mm
vs
519mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1381cm2
vs
2575cm2
|
Takes less floor space |
| General |
KEF Kube 15 MIE |
GoldenEar SuperSub X |
| Brand |
KEF |
GoldenEar |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
1400 watts |
| Frequency Response |
20-140 Hz |
12-250 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
1400-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
2 |
| Woofer Size |
15" |
8" |
| Woofer Composition |
Polypropylene |
Fiber |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
40-140 Hz |
n/a |
| Firing Direction |
n/a |
side |
Physical Specs |
|
|
| Height |
519.0mm (20.4") |
324.0mm (12.8") |
| Width |
500.0mm (19.7") |
356.0mm (14") |
| Depth |
515.0mm (20.3") |
388.0mm (15.3") |
| Weight |
27.50kg (60.5lbs) |
18.18kg (40lbs) |
| Enclosure |
Acoustic Suspension |
Passive Radiator |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
3 Years |
| Labor Warranty |
2 Years |
3 Years |