In this review, we will be comparing KUBE 8b and SUB8, two Powered Subwoofer speakers from KEF and Kanto. 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 KEF KUBE 8b and Kanto SUB8 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.KEF KUBE 8band Kanto SUB8 have the same driver set up: Both subwoofers have 1 x 8" drivers.
Frequency Response
KUBE 8b has a frequency range of 34-140 Hz whereas SUB8 has a frequency range of 35-175 Hz. With a minimum frequency of 34Hz, the KUBE 8b can go slightly deeper then the SUB8's min frequency of 35Hz.
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 KEF KUBE 8b and Kanto SUB8 have Acoustic Suspension type cabinets. 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.
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 KEF KUBE 8b's and Kanto SUB8's external dimensions. KEF KUBE 8b has external dimensions of 294.0 x 296.0 x 339.0mm (11-9/16 x 11-5/8 x 13-5/16inch) whereas Kanto SUB8 has external dimensions of 301.0 x 281.0 x 329.0mm (11-13/16 x 11-1/16 x 12-15/16inch).
Kanto SUB8 is 15mm narrower and 10mm less deeper than KEF KUBE 8b but it is also 7mm taller.
Below you can see the front view size comparison of KEF KUBE 8b and Kanto SUB8 in scale.
Comparison image of KEF KUBE 8b and Kanto SUB8 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 KEF KUBE 8b is approximately 1003.4cm2 / 155.5inch2 and base area of the Kanto SUB8 is approximately 924.5cm2 / 143.3inch2. The KUBE 8b requires 9% more surface area than the SUB8 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 KEF KUBE 8b weighs 11.36kg / 25lbs and the Kanto SUB8 weighs 7.82kg / 17.2lbs. This makes the KUBE 8b 45% heavier than the SUB8.
Here is a comparison of how KUBE 8b and SUB8's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of KEF KUBE 8b?
Here are the items that are included inside the box of KUBE 8b:
- Powered subwoofer
- 6.5-feet AC power cord
- Speaker-level input block
- User Manual
- Important Safety Information
- Warranty Information
What's in the Box of Kanto SUB8?
Here are the items that come with the SUB8:
- Powered subwoofer
- 6-feet AC power cord
- 9.75-feet mono-RCA cable
- User Manual
 Low Frequency Response |
34 Hz
vs
35 Hz
|
Generates deeper bass |
 Height |
294mm
vs
301mm
|
Easier to fit in smaller spaces |
 High Frequency Response |
175 Hz
vs
140 Hz
|
Generates higher frequency |
 Base Surface Area |
924cm2
vs
1003cm2
|
Takes less floor space |
 Price per pair* |
300USD
vs
600USD
|
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.
KEF KUBE 8b needs about 9% more floor area.
| General |
KEF KUBE 8b |
Kanto SUB8 |
| Brand |
KEF |
Kanto |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
125 watts |
| Frequency Response |
34-140 Hz |
35-175 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
125-watt RMS |
| Watts Peak (Max) |
n/a |
250-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
8" |
| Woofer Composition |
|
Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
40-140 Hz |
n/a |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
294.0mm (11.6") |
301.0mm (11.9") |
| Width |
296.0mm (11.7") |
281.0mm (11.1") |
| Depth |
339.0mm (13.3") |
329.0mm (13") |
| Weight |
11.36kg (25lbs) |
7.82kg (17.2lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
2 Years |
| Labor Warranty |
2 Years |
2 Years |
Different price classes - KEF KUBE 8b costs roughly 2x what Kanto SUB8 does. Before paying it, read the note below about two smaller subwoofers.
| Area | Better | Why |
|---|
| Bass depth | evenly matched | Effectively the same reach (34Hz vs 35Hz). |
| Amplifier power | A | KEF KUBE 8b has the bigger amplifier - 300W against 125W RMS, about 3.8dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | evenly matched | Near-identical radiating area (8" against 8"). |
| Enclosure | evenly matched | Both are sealed designs, so they roll off in much the same way. |
| Price | B | Kanto SUB8 costs less - $300 against $600, about 50% less. |
A KEF KUBE 8b B Kanto SUB8
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?
KEF KUBE 8b is ahead, but on only 1 of the measured areas, and it costs about 100% more. Kanto SUB8 is the sensible buy unless your room is large enough to need the extra. 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 $300 each, two Kanto SUB8 cost about $600 against $600 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.