In this review, we will be comparing Monitor XT12 and Windsor 12, two Powered Subwoofer speakers from Polk Audio and KLH. 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 KLH Windsor 12 first before getting into our more detailed comparison.
The sections below take each area in turn: driver and amplifier, frequency response, physical size and connectivity.
Drivers
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.Polk Monitor XT12and KLH Windsor 12 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 Windsor 12 has a frequency range of 30-160 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 Windsor 12'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
Both Polk Monitor XT12 and KLH Windsor 12 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
The size of a speaker can sometimes be 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 KLH Windsor 12'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 KLH Windsor 12 has external dimensions of 455.0 x 401.0 x 521.0mm (17-7/8 x 15-3/4 x 20-1/2inch).
Polk Monitor XT12 is 37mm shorter and 36mm less deeper than KLH Windsor 12 but it is also 7mm wider.
Below you can see the front view size comparison of Polk Monitor XT12 and KLH Windsor 12 in scale.
Comparison image of Polk Monitor XT12 and KLH Windsor 12 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 KLH Windsor 12 is approximately 2089.2cm2 / 323.8inch2. The Monitor XT12 requires 5% less surface area than the Windsor 12 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 KLH Windsor 12 weighs 20.19kg / 44.4lbs. This makes the Windsor 12 14% heavier than the Monitor XT12.
Here is a comparison of how Monitor XT12 and Windsor 12'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 subwoofer
- 6.5-feet AC power cord
- Grille
- Owners Manual
- Online registration card
What's in the Box of KLH Windsor 12?
Here are the items that come with the Windsor 12:
- Powered subwoofer
- Grille
- 9-feet AC power cord
- Manual
 Low Frequency Response |
24 Hz
vs
30 Hz
|
Generates deeper bass |
 Height |
418mm
vs
455mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1978cm2
vs
2089cm2
|
Takes less floor space |
 Price per pair* |
399USD
vs
800USD
|
costs less (*prices may change depending on the seller, location and time) |
Size, drawn to scale
Both subwoofers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same floor and pushed back to the same wall, so the bigger one visibly takes more of the room.
Near-identical footprints. KLH Windsor 12 stands 36mm further into the room. KLH Windsor 12 is 37mm taller.
| General |
Polk Monitor XT12 |
KLH Windsor 12 |
| Brand |
Polk Audio |
KLH |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
50 watts |
200 watts |
| Frequency Response |
24-160 Hz |
30-160 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 |
Composite |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
418.0mm (16.5") |
455.0mm (17.9") |
| Width |
408.0mm (16.1") |
401.0mm (15.8") |
| Depth |
485.0mm (19.1") |
521.0mm (20.5") |
| Weight |
17.73kg (39lbs) |
20.19kg (44.4lbs) |
| 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 |
Different price classes - KLH Windsor 12 costs roughly 2x what Polk Monitor XT12 does. Before paying it, read the note below about two smaller subwoofers.
| Area | Better | Why |
|---|
| Bass depth | A | Polk Monitor XT12 goes deeper - 24Hz against 30Hz. That gap covers the lowest notes of a five-string bass and a concert bass drum. |
| Amplifier power | B | KLH Windsor 12 has the bigger amplifier - 200W against 50W RMS, about 6dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | evenly matched | Near-identical radiating area (12" against 12"). |
| Enclosure | evenly matched | Both are ported designs, so they roll off in much the same way. |
| Speaker-level inputs | A | Polk Monitor XT12 takes a speaker-level connection as well as line level. That is what lets it work with an integrated amplifier or a vintage receiver that has no subwoofer output at all. |
| Warranty | A | Polk Monitor XT12 carries 3 years on parts against 2 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | A | Polk Monitor XT12 costs less - $399 against $800, about 50% less. |
A Polk Monitor XT12 B KLH Windsor 12
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both subwoofers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Polk Monitor XT12 is the easier recommendation: it leads on most of the measured areas and costs less. Take KLH Windsor 12 if one of the "depends" rows describes your room. Check your amplifier first: if it has no subwoofer or preamp output, Polk Monitor XT12 is the only one of these two you can connect at all. Two small subwoofers beat one big one in most rooms - a pair evens out the room modes in a way no single box can, whatever its specs. At $399 each, two Polk Monitor XT12 cost about $798 against $800 for one of the other, which is worth a thought.
One thing outweighs everything above: where the subwoofer stands. Room modes can add or remove 10dB or more at a given seat, which is far larger than any difference on this page. Before spending more, try the sub in two or three positions - the crawl test, where you put it in the listening seat and crawl the room to find where the bass sounds best, costs nothing and usually beats an upgrade.