In this review, we will be comparing Varro RS500-SB and KUBE 10b, two Powered Subwoofer speakers from ELAC 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 ELAC Varro RS500-SB and KEF KUBE 10b 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.ELAC Varro RS500-SBand KEF KUBE 10b have the same driver set up: Both subwoofers have 1 x 10" drivers.
Frequency Response
Varro RS500-SB has a frequency range of 18-150 Hz whereas KUBE 10b has a frequency range of 24-140 Hz. With a minimum frequency of 18Hz, the Varro RS500-SB can go significantly deeper on the low side and provide stronger bass compared to the KUBE 10b's min frequency of 24Hz.
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 ELAC Varro RS500-SB and KEF KUBE 10b 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 ELAC Varro RS500-SB's and KEF KUBE 10b's external dimensions. ELAC Varro RS500-SB has external dimensions of 381.0 x 361.0 x 388.0mm (15inch x 14-3/16inch x 15-1/4inch) whereas KEF KUBE 10b has external dimensions of 372.0 x 356.0 x 397.0mm (14-5/8 x 14 x 15-5/8inch).
KEF KUBE 10b is 5mm narrower and 9mm shorter than ELAC Varro RS500-SB but it is also 9mm deeper.
Below you can see the front view size comparison of ELAC Varro RS500-SB and KEF KUBE 10b in scale.
Comparison image of ELAC Varro RS500-SB and KEF KUBE 10b 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 ELAC Varro RS500-SB is approximately 1400.7cm2 / 217.1inch2 and base area of the KEF KUBE 10b is approximately 1413.3cm2 / 219.1inch2. The Varro RS500-SB requires 1% less surface area than the KUBE 10b 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 ELAC Varro RS500-SB weighs 20.85kg / 45.9lbs and the KEF KUBE 10b weighs 17.50kg / 38.5lbs. This makes the Varro RS500-SB 19% heavier than the KUBE 10b.
Here is a comparison of how Varro RS500-SB and KUBE 10b's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of ELAC Varro RS500-SB?
Here are the items that are included inside the box of Varro RS500-SB:
- Grill
- Power Cord
- 4 Spikes
What's in the Box of KEF KUBE 10b?
Here are the items that come with the KUBE 10b:
- Powered subwoofer
- 6.5-feet AC power cord
- Speaker-level input block
- User Manual
- Important Safety Information
- Warranty Information
 Low Frequency Response |
18 Hz
vs
24 Hz
|
Generates deeper bass |
 High Frequency Response |
150 Hz
vs
140 Hz
|
Generates higher frequency |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
 Base Surface Area |
1400cm2
vs
1413cm2
|
Takes less floor space |
 Ethernet Connection |
Yes
vs
No
|
High quality streaming over Ethernet |
 Height |
372mm
vs
381mm
|
Easier to fit in smaller spaces |
 Price per pair* |
750USD
vs
1299USD
|
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.
| General |
ELAC Varro RS500-SB |
KEF KUBE 10b |
| Brand |
ELAC |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
500 watts |
300 watts |
| Frequency Response |
18-150 Hz |
24-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
500-watt RMS |
300-watt RMS |
| Watts Peak (Max) |
1000-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
10" |
10" |
| Woofer Composition |
Aluminum |
|
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-140 Hz |
| Firing Direction |
bottom |
front |
Physical Specs |
|
|
| Height |
381.0mm (15") |
372.0mm (14.6") |
| Width |
361.0mm (14.2") |
356.0mm (14") |
| Depth |
388.0mm (15.3") |
397.0mm (15.6") |
| Weight |
20.85kg (45.9lbs) |
17.50kg (38.5lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Finish |
MDF |
n/a |
| Available Colors |
Gloss Black |
n/a |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| USB Port |
USB-A port for firmware updates |
n/a |
| Ethernet Port |
Yes |
n/a |
Other |
|
|
| Parts Warranty |
1 year |
2 Years |
| Labor Warranty |
1 year |
2 Years |
Different price classes - ELAC Varro RS500-SB costs roughly 1.7x what KEF KUBE 10b does. Before paying it, read the note below about two smaller subwoofers.
| Area | Better | Why |
|---|
| Bass depth | A | ELAC Varro RS500-SB goes deeper - 18Hz against 24Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | A | ELAC Varro RS500-SB 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 | evenly matched | Near-identical radiating area (10" against 10"). |
| Enclosure | evenly matched | Both are sealed designs, so they roll off in much the same way. |
| Setup and tuning | evenly matched | The same tuning tools on both (room correction and onboard DSP). |
| Speaker-level inputs | A | ELAC Varro RS500-SB 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. |
| Driver placement | depends | ELAC Varro RS500-SB fires down and KEF KUBE 10b fires front. A down-firing driver is more forgiving of a grille-less look and of a hard floor; a front-firing one is the safer choice on a thick carpet or a suspended timber floor. |
| Warranty | B | KEF KUBE 10b 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 | B | KEF KUBE 10b costs less - $750 against $1,299, about 42% less. |
A ELAC Varro RS500-SB B KEF KUBE 10b
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 Varro RS500-SB measures better, KEF KUBE 10b costs about 42% less. In a normal room, placement will make a bigger difference than the gap between these two. Check your amplifier first: if it has no subwoofer or preamp output, ELAC Varro RS500-SB 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 $750 each, two KEF KUBE 10b cost about $1,500 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.