In this review, we will be comparing SW-15 and KUBE 12b, two Powered Subwoofer speakers from Wharfedale and KEF. 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 Wharfedale SW-15 and KEF KUBE 12b 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 Wharfedale SW-15and KEF KUBE 12b have a single woofer setup however the Wharfedale SW-15's woofer is 15-inch whereas the KEF KUBE 12b features a 12-inch woofer.
Frequency Response
SW-15 has a frequency range of 30-120 Hz whereas KUBE 12b has a frequency range of 22-140 Hz. With a minimum frequency of 22Hz, the KUBE 12b can go significantly deeper on the low side and provide stronger bass compared to the SW-15'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 Wharfedale SW-15 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 KEF KUBE 12b have Acoustic Suspension type enclosure. Acoustic Suspension aka Sealed type subwoofers have enclosures that are sealed hence no ports or holes exists on the cabinet. Sealed designs helps to provide more accurate and tight bass responses compared to ported designs.
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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 Wharfedale SW-15's and KEF KUBE 12b's external dimensions. Wharfedale SW-15 has external dimensions of 570.0 x 493.0 x 615.0mm (22-7/16inch x 19-3/8inch x 24-3/16inch) whereas KEF KUBE 12b has external dimensions of 410.0 x 396.0 x 442.0mm (16-1/8 x 15-9/16 x 17-3/8inch).
Wharfedale SW-15 is clearly the larger of the two speakers. Its body is 97mm wider, 160mm taller and 173mm deeper than KEF KUBE 12b.
Below you can see the front view size comparison of Wharfedale SW-15 and KEF KUBE 12b in scale.
Comparison image of Wharfedale SW-15 and KEF KUBE 12b 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 Wharfedale SW-15 is approximately 3032.0cm2 / 470.0inch2 and base area of the KEF KUBE 12b is approximately 1750.3cm2 / 271.3inch2. The SW-15 requires 73% more surface area than the KUBE 12b 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 Wharfedale SW-15 weighs 31.57kg / 69.5lbs and the KEF KUBE 12b weighs 20.68kg / 45.5lbs. This makes the SW-15 53% heavier than the KUBE 12b.
Here is a comparison of how SW-15 and KUBE 12b's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of Wharfedale SW-15?
Here are the items that are included inside the box of SW-15:
- Powered subwoofer
- Grille
- 6.5-feet AC power cord
- User-feets Manual
What's in the Box of KEF KUBE 12b?
Here are the items that come with the KUBE 12b:
- Powered subwoofer
- 6.5-feet AC power cord
- Speaker-level input block
- User Manual
- Important Safety Information
- Warranty Information
 Woofer Size |
15 inches
vs
12 inches
|
Larger woofer |
| Low Frequency Response |
22 Hz
vs
30 Hz
|
Generates deeper bass |
 High Frequency Response |
140 Hz
vs
120 Hz
|
Generates higher frequency |
 Height |
410mm
vs
570mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1750cm2
vs
3032cm2
|
Takes less floor space |
 Price per pair* |
900USD
vs
1199USD
|
costs less (*prices may change depending on the seller, location and time) |
 Wireless Operation |
Optional
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.
Wharfedale SW-15 needs about 73% more floor area. Wharfedale SW-15 stands 173mm further into the room. Wharfedale SW-15 is 160mm taller.
| General |
Wharfedale SW-15 |
KEF KUBE 12b |
| Brand |
Wharfedale |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
400 watts |
300 watts |
| Frequency Response |
30-120 Hz |
22-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
400-watt RMS |
300-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
15" |
12" |
| Woofer Composition |
Paper |
|
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-140 Hz |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
570.0mm (22.4") |
410.0mm (16.1") |
| Width |
493.0mm (19.4") |
396.0mm (15.6") |
| Depth |
615.0mm (24.2") |
442.0mm (17.4") |
| Weight |
31.57kg (69.5lbs) |
20.68kg (45.5lbs) |
| Enclosure |
Bass Reflex |
Acoustic Suspension |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
2 Years |
| Labor Warranty |
3 Years |
2 Years |
A ported subwoofer against a sealed one. That is the most consequential line on this page: it decides how the bass rolls off, how it behaves in a small room, and how much output you get for the size of the box.
| Area | Better | Why |
|---|
| Bass depth | B | KEF KUBE 12b goes deeper - 22Hz against 30Hz. That gap covers the lowest notes of a five-string bass and a concert bass drum. |
| Amplifier power | A | Wharfedale SW-15 has the bigger amplifier - 400W against 300W RMS, about 1.2dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | Wharfedale SW-15 moves more air: 15" against 12" is 1.56x the cone area, not the 1.25x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | Wharfedale SW-15 is ported - a ported box gives more output low down for its size, at the cost of a steeper roll-off below tuning; KEF KUBE 12b is sealed - a sealed box rolls off gently and is usually the easier one to integrate in a small or awkward room. Neither is better in the abstract; ported tends to suit films and sealed tends to suit music, and both generalisations have exceptions. |
| Wireless option | depends | Only KEF KUBE 12b offers a wireless link (as a paid option). It decides where the sub can go if you cannot run a cable, and is worth nothing if you can. |
| Cabinet size | depends | KEF KUBE 12b is about 58% 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. |
| Warranty | A | Wharfedale SW-15 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 | B | KEF KUBE 12b costs less - $900 against $1,199, about 25% less. |
A Wharfedale SW-15 B KEF KUBE 12b
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?
The usual trade-off: Wharfedale SW-15 measures better, KEF KUBE 12b costs about 25% less. In a normal room, placement will make a bigger difference than the gap between these two. Films or music? If this is mainly a home cinema, Wharfedale SW-15 will hit harder for the money; if it is mainly for music in a normal-sized room, KEF KUBE 12b is usually the easier one to make sound right. If placement is the constraint - a corner, behind a sofa, under a desk - KEF KUBE 12b is the one that will actually go there, and a well-placed small subwoofer beats a badly-placed big one every time.
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.