In this review, we will be comparing Flexus Sub 100 and KUBE 10b, two Powered Subwoofer speakers from Klipsch 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 Klipsch Flexus Sub 100 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.Klipsch Flexus Sub 100and KEF KUBE 10b have the same driver set up: Both subwoofers have 1 x 10" drivers.
Frequency Response
Flexus Sub 100 has a frequency range of 26-250 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 Flexus Sub 100's min frequency of 26Hz.
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 Klipsch Flexus Sub 100 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 Klipsch Flexus Sub 100's and KEF KUBE 10b's external dimensions. Klipsch Flexus Sub 100 has external dimensions of 340.0 x 335.0 x 349.0mm (13-3/8 x 13-3/16 x 13-3/4inch) 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 clearly the larger of the two speakers. Its body is 21mm wider, 32mm taller and 48mm deeper than Klipsch Flexus Sub 100.
Size, drawn to scale
Both speakers 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 surface and pushed back to the same wall, so the deeper one visibly sticks out further.
KEF KUBE 10b needs about 21% more floor or shelf area. KEF KUBE 10b is 48mm deeper, so it stands that much further out from the wall. KEF KUBE 10b is 32mm taller.
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 Klipsch Flexus Sub 100 is approximately 1169.2cm2 / 181.2inch2 and base area of the KEF KUBE 10b is approximately 1413.3cm2 / 219.1inch2. The Flexus Sub 100 requires 17% 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 Klipsch Flexus Sub 100 weighs 9.40kg / 20.7lbs and the KEF KUBE 10b weighs 17.50kg / 38.5lbs. This makes the KUBE 10b 86% heavier than the Flexus Sub 100.
Here is a comparison of how Flexus Sub 100 and KUBE 10b's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 High Frequency Response |
250 Hz
vs
140 Hz
|
Generates higher frequency |
 Height |
340mm
vs
372mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1169cm2
vs
1413cm2
|
Takes less floor space |
 Price per pair* |
350USD
vs
750USD
|
costs less (*prices may change depending on the seller, location and time) |
 Low Frequency Response |
24 Hz
vs
26 Hz
|
Generates deeper bass |
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 21% more floor area. KEF KUBE 10b stands 48mm further into the room. KEF KUBE 10b is 32mm taller.
| General |
Klipsch Flexus Sub 100 |
KEF KUBE 10b |
| Brand |
Klipsch |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
80 watts |
300 watts |
| Frequency Response |
26-250 Hz |
24-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
80-watt RMS |
300-watt RMS |
| Watts Peak (Max) |
160-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
10" |
10" |
| Woofer Composition |
Paper |
|
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-140 Hz |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
340.0mm (13.4") |
372.0mm (14.6") |
| Width |
335.0mm (13.2") |
356.0mm (14") |
| Depth |
349.0mm (13.7") |
397.0mm (15.6") |
| Weight |
9.40kg (20.7lbs) |
17.50kg (38.5lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
5 Years |
2 Years |
| Labor Warranty |
5 Years |
2 Years |
Different price classes - KEF KUBE 10b costs roughly 2.1x what Klipsch Flexus Sub 100 does. Before paying it, read the note below about two smaller subwoofers.
| Area | Better | Why |
|---|
| Bass depth | evenly matched | Effectively the same reach (26Hz vs 24Hz). |
| Amplifier power | B | KEF KUBE 10b has the bigger amplifier - 300W against 80W RMS, about 5.7dB 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. |
| Cabinet size | depends | Klipsch Flexus Sub 100 is about 24% 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 | Klipsch Flexus Sub 100 carries 5 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 | A | Klipsch Flexus Sub 100 costs less - $350 against $750, about 53% less. |
A Klipsch Flexus Sub 100 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?
Neither runs away with it - they trade advantages. Let your room size and where the box can actually stand settle it. 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 $350 each, two Klipsch Flexus Sub 100 cost about $700 against $750 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.