In this review, we will be comparing SubSeries BP8 and KUBE 10b, two Powered Subwoofer speakers from PSB 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 PSB SubSeries BP8 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.Both PSB SubSeries BP8and KEF KUBE 10b have a single woofer setup however the PSB SubSeries BP8's woofer is 8-inch whereas the KEF KUBE 10b features a 10-inch woofer.
Frequency Response
SubSeries BP8 has a frequency range of 25-150 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 SubSeries BP8's min frequency of 25Hz.
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 PSB SubSeries BP8 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 PSB SubSeries BP8's and KEF KUBE 10b's external dimensions. PSB SubSeries BP8 has external dimensions of 355 x 330 x 330mm (14 x 13 x 13 inch) 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 26mm wider, 17mm taller and 67mm deeper than PSB SubSeries BP8.
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 30% more floor or shelf area. KEF KUBE 10b is 67mm deeper, so it stands that much further out from the wall. KEF KUBE 10b is 17mm 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 PSB SubSeries BP8 is approximately 1089.0cm2 / 168.8inch2 and base area of the KEF KUBE 10b is approximately 1413.3cm2 / 219.1inch2. The SubSeries BP8 requires 23% 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 PSB SubSeries BP8 weighs 19.10kg / 42lbs and the KEF KUBE 10b weighs 17.50kg / 38.5lbs. This makes the SubSeries BP8 9% heavier than the KUBE 10b.
Here is a comparison of how SubSeries BP8 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 PSB SubSeries BP8?
Here are the items that are included inside the box of SubSeries BP8:
- Powered subwoofer
- Detachable grille
- 8-feet Power cord
- Owners Guide
- Specifications sheet
- Warranty Card
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 |
 Height |
355mm
vs
372mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1089cm2
vs
1413cm2
|
Takes less floor space |
 Woofer Size |
10 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
24 Hz
vs
25 Hz
|
Generates deeper bass |
 Price per pair* |
750USD
vs
1499USD
|
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 10b needs about 30% more floor area. KEF KUBE 10b stands 67mm further into the room. KEF KUBE 10b is 17mm taller.
| General |
PSB SubSeries BP8 |
KEF KUBE 10b |
| Brand |
PSB |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
500 watts |
300 watts |
| Frequency Response |
25-150 Hz |
24-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
500-watt RMS |
300-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
10" |
| Woofer Composition |
Carbon Fibre |
|
| Woofer Surround Material |
High Density Rubber |
n/a |
| 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 |
355.0mm (14") |
372.0mm (14.6") |
| Width |
330.0mm (13") |
356.0mm (14") |
| Depth |
330.0mm (13") |
397.0mm (15.6") |
| Weight |
19.10kg (42lbs) |
17.50kg (38.5lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Available Colors |
Satin Black, Satin White |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
1 Year |
2 Years |
| Labor Warranty |
1 Year |
2 Years |
Different price classes - PSB SubSeries BP8 costs roughly 2x what KEF KUBE 10b does. Before paying it, read the note below about two smaller subwoofers.
| Area | Better | Why |
|---|
| Bass depth | evenly matched | Effectively the same reach (25Hz vs 24Hz). |
| Amplifier power | A | PSB SubSeries BP8 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 | KEF KUBE 10b moves more air: 10" against 8" is 1.56x the cone area, not the 1.25x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | evenly matched | Both are sealed designs, so they roll off in much the same way. |
| Speaker-level inputs | A | PSB SubSeries BP8 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. |
| Cabinet size | depends | PSB SubSeries BP8 is about 26% 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 | 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 $1,499, about 50% less. |
A PSB SubSeries BP8 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. Check your amplifier first: if it has no subwoofer or preamp output, PSB SubSeries BP8 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 $1,499 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.