In this review, we will be comparing Monitor XT12 and Radius 380, two Powered Subwoofer speakers from Polk Audio and Monitor 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 Polk Monitor XT12 and Monitor Audio Radius 380 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 Monitor Audio Radius 380 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.Both Polk Monitor XT12and Monitor Audio Radius 380 have a single woofer setup however the Polk Monitor XT12's woofer is 12-inch whereas the Monitor Audio Radius 380 features a 8-inch woofer.
Frequency Response
Monitor XT12 has a frequency range of 24-160 Hz whereas Radius 380 has a frequency range of 30-120 Hz. With a minimum frequency of 24Hz, the Monitor XT12 can go significantly deeper on the low side and provide stronger bass compared to the Radius 380's min frequency of 30Hz.
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 Polk Monitor XT12 has a Bass Reflex type cabinet. 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. On the other hand the Monitor Audio Radius 380 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 Polk Monitor XT12's and Monitor Audio Radius 380'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 Monitor Audio Radius 380 has external dimensions of 308.0 x 291.0 x 345.0mm ( 12-1/8 x 11-7/16 x 13-9/16inch) .
Polk Monitor XT12 is clearly the larger of the two speakers. Its body is 117mm wider, 110mm taller and 140mm deeper than Monitor Audio Radius 380.
Below you can see the front view size comparison of Polk Monitor XT12 and Monitor Audio Radius 380 in scale.
Comparison image of Polk Monitor XT12 and Monitor Audio Radius 380 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 Monitor Audio Radius 380 is approximately 1004.0cm2 / 155.6inch2. The Monitor XT12 requires 97% more surface area than the Radius 380 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 Polk Monitor XT12 weighs 17.73kg / 39lbs and the Monitor Audio Radius 380 weighs 10.18kg / 22.4lbs. This makes the Monitor XT12 74% heavier than the Radius 380.
Here is a comparison of how Monitor XT12 and Radius 380'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 Monitor Audio Radius 380?
Here are the items that come with the Radius 380:
Powered sub6-feet AC power cord10.75-feet Mono minijack cableOwners ManualImportant Safety Instructions
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
24 Hz
vs
30 Hz
|
Generates deeper bass |
 High Frequency Response |
160k Hz
vs
120k Hz
|
Generates higher frequency |
 Price per pair* |
399USD
vs
875USD
|
costs less (*prices may change depending on the seller, location and time) |
 Height |
308mm
vs
418mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1004cm2 (291x345mm)
vs
1978cm2 (408x485mm)
|
Takes less floor space |
| General |
Polk Monitor XT12 |
Monitor Audio Radius 380 |
| Brand |
Polk Audio |
Monitor Audio |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
50 watts |
200 watts |
| Frequency Response |
24-160 Hz |
30-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
50-watt RMS |
200-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
8" |
| Woofer Composition |
Bi-laminate paper |
C-CAM |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
side |
Physical Specs |
|
|
| Height |
418.0mm (16.5") |
308.0mm (12.1") |
| Width |
408.0mm (16.1") |
291.0mm (11.5") |
| Depth |
485.0mm (19.1") |
345.0mm (13.6") |
| Weight |
17.73kg (39lbs) |
10.18kg (22.4lbs) |
| Enclosure |
Bass Reflex |
Passive Radiator |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
2 Years |
| Labor Warranty |
3 Years |
2 Years |