In this review, we will be comparing KC92 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 KC92 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 KC92 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 KC92 and Polk Monitor XT12 have a totally different setup: the KEF KC92 features 2 x 9-inch drivers whereas the Monitor XT12 features 1 x 12-inch drivers.
Frequency Response
KC92 has a frequency range of 11-200 Hz whereas Monitor XT12 has a frequency range of 24-160 Hz. With a minimum frequency of 11Hz, the KC92 can go significantly deeper on the low side and provide stronger bass compared to 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 KC92 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 KC92's and Polk Monitor XT12's external dimensions. KEF KC92 has external dimensions of 352.5 x 330 x 360.5 mm ( 13.88 x 13.00 x 14.19 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 78mm wider, 66mm taller and 124mm deeper than KEF KC92.
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 KC92 is approximately 1191.3cm2 / 184.7inch2 and base area of the Polk Monitor XT12 is approximately 1978.8cm2 / 306.7inch2. The KC92 requires 40% 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 KC92 weighs 20.00kg / 44lbs and the Polk Monitor XT12 weighs 17.73kg / 39lbs. This makes the KC92 13% heavier than the Monitor XT12.
Here is a comparison of how KC92 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 KC92?
Here are the items that are included inside the box of KC92:
KC92 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
 Number of Woofers |
2
vs
1
|
More woofers |
| Low Frequency Response |
11 Hz
vs
24 Hz
|
Generates deeper bass |
 High Frequency Response |
200k Hz
vs
160k Hz
|
Generates higher frequency |
 Height |
352mm
vs
418mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1191cm2 (330x361mm)
vs
1978cm2 (408x485mm)
|
Takes less floor space |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
| Woofer Size |
12 inches
vs
9 inches
|
Larger woofer |
 Price per pair* |
399USD
vs
1999USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
KEF KC92 |
Polk Monitor XT12 |
| Brand |
KEF |
Polk Audio |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
1000 watts |
50 watts |
| Frequency Response |
11-200 Hz |
24-160 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
1000-watt RMS |
50-watt RMS |
Drivers |
|
|
| Woofer Quantity |
2 |
1 |
| Woofer Size |
9" |
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 |
352.0mm (13.9") |
418.0mm (16.5") |
| Width |
330.0mm (13") |
408.0mm (16.1") |
| Depth |
361.0mm (14.2") |
485.0mm (19.1") |
| Weight |
20.00kg (44lbs) |
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 |