In this review, we will be comparing Varro PS250-BK 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 PS250-BK 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 PS250-BKand KEF KUBE 10b have the same driver set up: Both subwoofers have 1 x 10" drivers.
Frequency Response
Varro PS250-BK has a frequency range of 27-150 Hz whereas KUBE 10b has a frequency range of 24-140 Hz. With a minimum frequency of 24Hz, the KUBE 10b can go slightly deeper then the Varro PS250-BK's min frequency of 27Hz.
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 ELAC Varro PS250-BK 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 10b 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.
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 PS250-BK's and KEF KUBE 10b's external dimensions. ELAC Varro PS250-BK has external dimensions of 381.0 x 361.0 x 361.0mm (15inch x 14-3/16inch x 14-3/16inch) 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 PS250-BK but it is also 36mm deeper.
Below you can see the front view size comparison of ELAC Varro PS250-BK and KEF KUBE 10b in scale.
Comparison image of ELAC Varro PS250-BK 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 PS250-BK is approximately 1303.2cm2 / 202.0inch2 and base area of the KEF KUBE 10b is approximately 1413.3cm2 / 219.1inch2. The Varro PS250-BK requires 8% 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 PS250-BK weighs 16.44kg / 36.2lbs and the KEF KUBE 10b weighs 17.50kg / 38.5lbs. This makes the KUBE 10b 6% heavier than the Varro PS250-BK.
Here is a comparison of how Varro PS250-BK 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 PS250-BK?
Here are the items that are included inside the box of Varro PS250-BK:
- 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
 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 |
1303cm2
vs
1413cm2
|
Takes less floor space |
 Price per pair* |
649USD
vs
750USD
|
costs less (*prices may change depending on the seller, location and time) |
 Low Frequency Response |
24 Hz
vs
27 Hz
|
Generates deeper bass |
 Height |
372mm
vs
381mm
|
Easier to fit in smaller spaces |
 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.
KEF KUBE 10b needs about 8% more floor area. KEF KUBE 10b stands 36mm further into the room.
| General |
ELAC Varro PS250-BK |
KEF KUBE 10b |
| Brand |
ELAC |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
250 watts |
300 watts |
| Frequency Response |
27-150 Hz |
24-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
250-watt RMS |
300-watt RMS |
| Watts Peak (Max) |
500-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
10" |
10" |
| Woofer Composition |
Treated paper |
|
| 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 |
361.0mm (14.2") |
397.0mm (15.6") |
| Weight |
16.44kg (36.2lbs) |
17.50kg (38.5lbs) |
| Enclosure |
Bass Reflex |
Acoustic Suspension |
| Finish |
MDF |
n/a |
| Available Colors |
Black |
n/a |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| USB Port |
USB-A port for firmware updates |
n/a |
Other |
|
|
| Parts Warranty |
1 year |
2 Years |
| Labor Warranty |
1 year |
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 10b goes deeper - 24Hz against 27Hz. A real difference, though most music has little content below 27Hz. |
| Amplifier power | evenly matched | Much the same amplifier (250W vs 300W RMS) - under 1dB apart. |
| Driver area | evenly matched | Near-identical radiating area (10" against 10"). |
| Enclosure | depends | ELAC Varro PS250-BK 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 10b 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. |
| Setup and tuning | evenly matched | The same tuning tools on both (room correction and onboard DSP). |
| Wireless option | depends | Only KEF KUBE 10b 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. |
| Driver placement | depends | ELAC Varro PS250-BK 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 | A | ELAC Varro PS250-BK costs less - $649 against $750, about 13% less. |
A ELAC Varro PS250-BK 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: KEF KUBE 10b measures better, ELAC Varro PS250-BK costs about 13% 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 Varro PS250-BK will hit harder for the money; if it is mainly for music in a normal-sized room, KEF KUBE 10b is usually the easier one to make sound right.
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.