In this review, we will be comparing Kube 12 MIE and Monitor XT12, two Powered Subwoofer speakers from KEF and Polk Audio. 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 12 MIE and Polk Monitor XT12 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 12 MIE and Polk Monitor XT12 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 12 MIEand Polk Monitor XT12 have the same driver set up: Both subwoofers have 1 x 12" drivers.
Frequency Response
Kube 12 MIE has a frequency range of 22-140 Hz whereas Monitor XT12 has a frequency range of 24-160 Hz. With a minimum frequency of 22Hz, the Kube 12 MIE can go slightly deeper then the Monitor XT12's min frequency of 24Hz.
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 12 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 Polk Monitor XT12 have Bass Reflex type enclosure. Bass Reflex type subwoofers (aka Ported, Vented or Reflex Port) have enclosures that uses a port, hole or vent cut into the cabinet. Ported designs are generally more efficient than the 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 12 MIE's and Polk Monitor XT12's external dimensions. KEF Kube 12 MIE has external dimensions of 410 x 393 x 410 mm ( 16.1 x 15.5 x 16.1 in) whereas Polk Monitor XT12 has external dimensions of 418.0 x 408.0 x 485.0mm ( 16-7/16inch x 16-1/16inch x 19-1/16inch ) .
Polk Monitor XT12 is clearly the larger of the two speakers. Its body is 15mm wider, 8mm taller and 75mm deeper than KEF Kube 12 MIE.
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 12 MIE is approximately 1611.3cm2 / 249.8inch2 and base area of the Polk Monitor XT12 is approximately 1978.8cm2 / 306.7inch2. The Kube 12 MIE requires 19% less surface area than the Monitor XT12 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 Kube 12 MIE weighs 18.60kg / 40.9lbs and the Polk Monitor XT12 weighs 17.73kg / 39lbs. This makes the Kube 12 MIE 5% heavier than the Monitor XT12.
Here is a comparison of how Kube 12 MIE and Monitor XT12'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 12 MIE?
Here are the items that are included inside the box of Kube 12 MIE:
Kube 12 MIE subwoofer Power cord Euroblock speaker level connector User manual and warranty information
What's in the Box of Polk Monitor XT12?
Here are the items that come with the Monitor XT12:
Black powered subwoofer6.5-feet AC power cordGrilleOwners ManualOnline registration card
 Low Frequency Response |
22 Hz
vs
24 Hz
|
Generates deeper bass |
 Height |
410mm
vs
418mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1611cm2 (393x410mm)
vs
1978cm2 (408x485mm)
|
Takes less floor space |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
 High Frequency Response |
160k Hz
vs
140k Hz
|
Generates higher frequency |
 Price per pair* |
399USD
vs
999USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
KEF Kube 12 MIE |
Polk Monitor XT12 |
| Brand |
KEF |
Polk Audio |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
50 watts |
| Frequency Response |
22-140 Hz |
24-160 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
50-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
12" |
| Woofer Composition |
Polypropylene |
Bi-laminate paper |
| 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 |
410.0mm (16.1") |
418.0mm (16.5") |
| Width |
393.0mm (15.5") |
408.0mm (16.1") |
| Depth |
410.0mm (16.1") |
485.0mm (19.1") |
| Weight |
18.60kg (40.9lbs) |
17.73kg (39lbs) |
| Enclosure |
Acoustic Suspension |
Bass Reflex |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
3 Years |
| Labor Warranty |
2 Years |
3 Years |