In this review, we will be comparing Thetis 300 and Monitor XT12, two Powered Subwoofer speakers from Triangle 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 Triangle Thetis 300 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 Triangle Thetis 300 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.Both Triangle Thetis 300and Polk Monitor XT12 have a single woofer setup however the Triangle Thetis 300's woofer is 8-inch whereas the Polk Monitor XT12 features a 12-inch woofer.
Frequency Response
Thetis 300 has a frequency range of 32-120 Hz whereas Monitor XT12 has a frequency range of 24-160 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 Thetis 300's min frequency of 32Hz.
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 Triangle Thetis 300 and Polk Monitor XT12 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.
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 Triangle Thetis 300's and Polk Monitor XT12's external dimensions. Triangle Thetis 300 has external dimensions of 340.0 x 300.0 x 300.0mm ( 13-3/8 x 11-13/16 x 11-13/16inch) 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 108mm wider, 78mm taller and 185mm deeper than Triangle Thetis 300.
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 Triangle Thetis 300 is approximately 900.0cm2 / 139.5inch2 and base area of the Polk Monitor XT12 is approximately 1978.8cm2 / 306.7inch2. The Thetis 300 requires 55% 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 Triangle Thetis 300 weighs 10.60kg / 23.3lbs and the Polk Monitor XT12 weighs 17.73kg / 39lbs. This makes the Monitor XT12 67% heavier than the Thetis 300.
Here is a comparison of how Thetis 300 and Monitor XT12's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Height |
340mm
vs
418mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
900cm2
vs
1978cm2
|
Takes less floor space |
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
24 Hz
vs
32 Hz
|
Generates deeper bass |
 High Frequency Response |
160k Hz
vs
120k Hz
|
Generates higher frequency |
 Price per pair* |
399USD
vs
650USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Triangle Thetis 300 |
Polk Monitor XT12 |
| Brand |
Triangle |
Polk Audio |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
150 watts |
50 watts |
| Frequency Response |
32-120 Hz |
24-160 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
150-watt RMS |
50-watt RMS |
| Watts Peak (Max) |
250-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
12" |
| Woofer Composition |
Paper composite |
Bi-laminate paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
340.0mm (13.4") |
418.0mm (16.5") |
| Width |
300.0mm (11.8") |
408.0mm (16.1") |
| Depth |
300.0mm (11.8") |
485.0mm (19.1") |
| Weight |
10.60kg (23.3lbs) |
17.73kg (39lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
5 Years |
3 Years |
| Labor Warranty |
5 Years |
3 Years |