In this review, we will be comparing Monitor XT12 and R-121SW, two Powered Subwoofer speakers from Polk Audio and Klipsch. 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 Polk Monitor XT12 and Klipsch R-121SW first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the Polk Monitor XT12 and Klipsch R-121SW 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.Polk Monitor XT12and Klipsch R-121SW have the same driver set up: Both subwoofers have 1 x 12" drivers.
Frequency Response
Monitor XT12 has a frequency range of 24-160 Hz whereas R-121SW has a frequency range of 28-120 Hz. With a minimum frequency of 24Hz, the Monitor XT12 can go slightly deeper then the R-121SW's min frequency of 28Hz.
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 Polk Monitor XT12 and Klipsch R-121SW have Bass Reflex type cabinets. 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.
Klipsch R-121SW Port
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 Polk Monitor XT12's and Klipsch R-121SW's external dimensions. 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 ) whereas Klipsch R-121SW has external dimensions of 423.0 x 407.0 x 532.0mm ( 16-5/8inch x 16inch x 20-15/16inch ) .
Polk Monitor XT12 is 5mm shorter and 47mm less deeper than Klipsch R-121SW but it is also 1mm wider.
Below you can see the front view size comparison of Polk Monitor XT12 and Klipsch R-121SW in scale.
Comparison image of Polk Monitor XT12 and Klipsch R-121SW 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 Polk Monitor XT12 is approximately 1978.8cm2 / 306.7inch2 and base area of the Klipsch R-121SW is approximately 2165.2cm2 / 335.6inch2. The Monitor XT12 requires 9% less surface area than the R-121SW 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 Polk Monitor XT12 weighs 17.73kg / 39lbs and the Klipsch R-121SW weighs 16.00kg / 35.2lbs. This makes the Monitor XT12 11% heavier than the R-121SW.
Here is a comparison of how Monitor XT12 and R-121SW's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of Polk Monitor XT12?
Here are the items that are included inside the box of Monitor XT12:
Black powered subwoofer6.5-feet AC power cordGrilleOwners ManualOnline registration card
What's in the Box of Klipsch R-121SW?
Here are the items that come with the R-121SW:
Powered subwooferGrille6.5-feet AC power cordUser ManualImportant Safety InstructionsWarranty Information
 Low Frequency Response |
24 Hz
vs
28 Hz
|
Generates deeper bass |
 High Frequency Response |
160k Hz
vs
120k Hz
|
Generates higher frequency |
 Height |
418mm
vs
423mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1978cm2
vs
2165cm2
|
Takes less floor space |
 Price per pair* |
399USD
vs
599USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Polk Monitor XT12 |
Klipsch Reference R-121SW |
| Brand |
Polk Audio |
Klipsch |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
50 watts |
200 watts |
| Frequency Response |
24-160 Hz |
28-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
50-watt RMS |
200-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
12" |
| Woofer Composition |
Bi-laminate paper |
Spun-Copper TCP |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
418.0mm (16.5") |
423.0mm (16.7") |
| Width |
408.0mm (16.1") |
407.0mm (16") |
| Depth |
485.0mm (19.1") |
532.0mm (20.9") |
| Weight |
17.73kg (39lbs) |
16.00kg (35.2lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
2 Years |
| Labor Warranty |
3 Years |
2 Years |