In this review, we will be comparing Monitor XT12 and Sub Air, two Powered Subwoofer speakers from Polk Audio and Focal. 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 Focal Sub Air 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.Both Polk Monitor XT12and Focal Sub Air have a single woofer setup however the Polk Monitor XT12's woofer is 12-inch whereas the Focal Sub Air features a 8-inch woofer.
Frequency Response
Monitor XT12 has a frequency range of 24-160 Hz whereas Sub Air has a frequency range of 40-200 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 Sub Air's min frequency of 40Hz.
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 Focal Sub Air 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 Focal Sub Air'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 Focal Sub Air has external dimensions of 410.0 x 362.0 x 162.0mm (16-1/8 x 14-1/4 x 6-3/8inch).
Polk Monitor XT12 is clearly the larger of the two speakers. Its body is 46mm wider, 8mm taller and 323mm deeper than Focal Sub Air.
Below you can see the front view size comparison of Polk Monitor XT12 and Focal Sub Air in scale.
Comparison image of Polk Monitor XT12 and Focal Sub Air 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 Focal Sub Air is approximately 586.4cm2 / 90.9inch2. The Monitor XT12 requires 237% more surface area than the Sub Air 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 Focal Sub Air weighs 7.73kg / 17lbs. This makes the Monitor XT12 129% heavier than the Sub Air.
Here is a comparison of how Monitor XT12 and Sub Air'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 Focal Sub Air?
Here are the items that come with the Sub Air:
- Wireless powered subwoofer
- Wireless transmitter
- AC power adapter (attached 6-feet DC cord)
- AC power plug insert (2-prong)
- 8-feet AC power cord
- 4 Rubber feet
- 2 Brackets
- Four M4 x 10mm machine screws
- Four M4 x 17mm machine screws
- 4 Wood-screws
- 4 Wall-anchors
- User Manual
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
24 Hz
vs
40 Hz
|
Generates deeper bass |
 Price per pair* |
399USD
vs
1299USD
|
costs less (*prices may change depending on the seller, location and time) |
 High Frequency Response |
200 Hz
vs
160 Hz
|
Generates higher frequency |
 Height |
410mm
vs
418mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
586cm2
vs
1978cm2
|
Takes less floor space |
 Wireless Operation |
Yes
vs
No
|
Connect your subwoofer to your system wireless |
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.
Polk Monitor XT12 needs about 237% more floor area. Polk Monitor XT12 stands 323mm further into the room.
| General |
Polk Monitor XT12 |
Focal Sub Air |
| Brand |
Polk Audio |
Focal |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
50 watts |
110 watts |
| Frequency Response |
24-160 Hz |
40-200 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
50-watt RMS |
110-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
8" |
| Woofer Composition |
Bi-laminate paper |
Cellulose Pulp |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
418.0mm (16.5") |
410.0mm (16.1") |
| Width |
408.0mm (16.1") |
362.0mm (14.3") |
| Depth |
485.0mm (19.1") |
162.0mm (6.4") |
| Weight |
17.73kg (39lbs) |
7.73kg (17lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
3 Years |
| Labor Warranty |
3 Years |
3 Years |
Two quite different sizes of subwoofer. Room volume decides this more than anything else on the page: a big driver in a small room is wasted, and a small one in a large room is worked to death.
| Area | Better | Why |
|---|
| Bass depth | A | Polk Monitor XT12 goes deeper - 24Hz against 40Hz. That gap covers the lowest notes of a five-string bass and a concert bass drum. |
| Amplifier power | B | Focal Sub Air has the bigger amplifier - 110W against 50W RMS, about 3.4dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | Polk Monitor XT12 moves more air: 12" against 8" is 2.25x the cone area, not the 1.5x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| 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. |
| Wireless option | depends | Only Focal Sub Air offers a wireless link. It decides where the sub can go if you cannot run a cable, and is worth nothing if you can. |
| Cabinet size | depends | Focal Sub Air is about 71% smaller by volume. In a subwoofer that is a real trade rather than a preference: box volume is how you get output low down without a bigger amplifier. |
| Price | A | Polk Monitor XT12 costs less - $399 against $1,299, about 69% less. |
A Polk Monitor XT12 B Focal Sub Air
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 Focal Sub Air 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 $1,299 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.