In this review, we will be comparing KUBE 8b and Debut 2.0 SUB3030, two Powered Subwoofer speakers from KEF and ELAC. 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 ELAC Debut 2.0 SUB3030 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.
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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 KEF KUBE 8band ELAC Debut 2.0 SUB3030 have a single woofer setup however the KEF KUBE 8b's woofer is 8-inch whereas the ELAC Debut 2.0 SUB3030 features a 12-inch woofer.
Frequency Response
KUBE 8b has a frequency range of 34-140 Hz whereas Debut 2.0 SUB3030 has a frequency range of 25-150 Hz. With a minimum frequency of 25Hz, the Debut 2.0 SUB3030 can go significantly deeper on the low side and provide stronger bass compared to the KUBE 8b's min frequency of 34Hz.
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 KEF KUBE 8b has a Acoustic Suspension type cabinet. 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. On the other hand the ELAC Debut 2.0 SUB3030 have Passive radiator type enclosure.
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 ELAC Debut 2.0 SUB3030'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 ELAC Debut 2.0 SUB3030 has external dimensions of 462.0 x 451.0 x 464.0mm (18-3/16 x 17-3/4 x 18-1/4inch).
ELAC Debut 2.0 SUB3030 is clearly the larger of the two speakers. Its body is 155mm wider, 168mm taller and 125mm deeper than KEF KUBE 8b.
Below you can see the front view size comparison of KEF KUBE 8b and ELAC Debut 2.0 SUB3030 in scale.
Comparison image of KEF KUBE 8b and ELAC Debut 2.0 SUB3030 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 ELAC Debut 2.0 SUB3030 is approximately 2092.6cm2 / 324.4inch2. The KUBE 8b requires 52% less surface area than the Debut 2.0 SUB3030 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 KEF KUBE 8b weighs 11.36kg / 25lbs and the ELAC Debut 2.0 SUB3030 weighs 22.80kg / 50.2lbs. This makes the Debut 2.0 SUB3030 101% heavier than the KUBE 8b.
Here is a comparison of how KUBE 8b and Debut 2.0 SUB3030'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 ELAC Debut 2.0 SUB3030?
Here are the items that come with the Debut 2.0 SUB3030:
- Powered subwoofer
- 9-feet AC power cord
- 4 Spikes
- 4 Hex-nuts
- Operating Instructions
 Height |
294mm
vs
462mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1003cm2
vs
2092cm2
|
Takes less floor space |
 Price per pair* |
600USD
vs
900USD
|
costs less (*prices may change depending on the seller, location and time) |
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
25 Hz
vs
34 Hz
|
Generates deeper bass |
 High Frequency Response |
150 Hz
vs
140 Hz
|
Generates higher frequency |
| General |
KEF KUBE 8b |
ELAC Debut 2.0 SUB3030 |
| Brand |
KEF |
ELAC |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
500 watts |
| Frequency Response |
34-140 Hz |
25-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
500-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
12" |
| Woofer Composition |
|
Doped Paper |
| Woofer Surround Material |
n/a |
Rubber |
| 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") |
462.0mm (18.2") |
| Width |
296.0mm (11.7") |
451.0mm (17.8") |
| Depth |
339.0mm (13.3") |
464.0mm (18.3") |
| Weight |
11.36kg (25lbs) |
22.80kg (50.2lbs) |
| Enclosure |
Acoustic Suspension |
Passive radiator |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
1 Year |
| Labor Warranty |
2 Years |
1 Year |
A sealed subwoofer against a passive radiator 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 | ELAC Debut 2.0 SUB3030 goes deeper - 25Hz against 34Hz. That gap covers the lowest notes of a five-string bass and a concert bass drum. |
| Amplifier power | B | ELAC Debut 2.0 SUB3030 has the bigger amplifier - 500W against 300W RMS, about 2.2dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | ELAC Debut 2.0 SUB3030 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 | depends | KEF KUBE 8b is sealed - a sealed box rolls off gently and is usually the easier one to integrate in a small or awkward room; ELAC Debut 2.0 SUB3030 is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet. Neither is better in the abstract; ported tends to suit films and sealed tends to suit music, and both generalisations have exceptions. |
| Cabinet size | depends | KEF KUBE 8b is about 69% 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 | KEF KUBE 8b carries 2 years on parts against 1 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | A | KEF KUBE 8b costs less - $600 against $900, about 33% less. |
A KEF KUBE 8b B ELAC Debut 2.0 SUB3030
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: ELAC Debut 2.0 SUB3030 measures better, KEF KUBE 8b costs about 33% 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, ELAC Debut 2.0 SUB3030 will hit harder for the money; if it is mainly for music in a normal-sized room, KEF KUBE 8b is usually the easier one to make sound right. If placement is the constraint - a corner, behind a sofa, under a desk - KEF KUBE 8b 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.