In this review, we will be comparing T 9x and KC92, two Powered Subwoofer speakers from REL 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 REL T 9x and KEF KC92 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.REL T 9x and KEF KC92 have a totally different setup: the REL T 9x features 1 x 10-inch drivers whereas the KC92 features 2 x 9-inch drivers.
Frequency Response
T 9x has a frequency range of 27-120 Hz whereas KC92 has a frequency range of 11-200 Hz. With a minimum frequency of 11Hz, the KC92 can go significantly deeper on the low side and provide stronger bass compared to the T 9x'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
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 REL T 9x's and KEF KC92's external dimensions. REL T 9x has external dimensions of 344.5 x 371.5 x 465.1mm () whereas KEF KC92 has external dimensions of 352.5 x 330 x 360.5 mm (13.88 x 13.00 x 14.19 in).
KEF KC92 is 41.5mm narrower and 104.1mm less deeper than REL T 9x but it is also 7.5mm 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 REL T 9x is approximately 1727.8cm2 / 267.8inch2 and base area of the KEF KC92 is approximately 1191.3cm2 / 184.7inch2. The T 9x requires 45% more surface area than the KC92 which gives it a small disadvantage 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 REL T 9x weighs 20.64kg / 45.4lbs and the KEF KC92 weighs 20.00kg / 44lbs. This makes the T 9x 3% heavier than the KC92.
Here is a comparison of how T 9x and KC92's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Woofer Size |
10 inches
vs
9 inches
|
Larger woofer |
 Height |
344mm
vs
352mm
|
Easier to fit in smaller spaces |
 Price per pair* |
1699USD
vs
1999USD
|
costs less (*prices may change depending on the seller, location and time) |
| Number of Woofers |
2
vs
1
|
More woofers |
| Low Frequency Response |
11 Hz
vs
27 Hz
|
Generates deeper bass |
 High Frequency Response |
200 Hz
vs
120 Hz
|
Generates higher frequency |
 Base Surface Area |
1191cm2
vs
1727cm2
|
Takes less floor space |
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.
REL T 9x needs about 45% more floor area. REL T 9x stands 104mm further into the room.
| General |
REL T 9x |
KEF KC92 |
| Brand |
REL |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
27-120 Hz |
11-200 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
1000-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
2 |
| Woofer Size |
10" |
9" |
| Woofer Composition |
|
Polypropylene |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-140 Hz |
Physical Specs |
|
|
| Height |
344.5mm (13.6") |
352.0mm (13.9") |
| Width |
371.5mm (14.6") |
330.0mm (13") |
| Depth |
465.1mm (18.3") |
361.0mm (14.2") |
| Weight |
20.64kg (45.4lbs) |
20.00kg (44lbs) |
| Enclosure |
|
Acoustic Suspension |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
2 Years |
| Labor Warranty |
3 Years |
2 Years |
A passive radiator 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 KC92 goes deeper - 11Hz against 27Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | B | KEF KC92 has the bigger amplifier - 1000W against 300W RMS, about 5.2dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | KEF KC92 moves more air: 2 x 9" against 10" is 1.62x the cone area, not the 1.27x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | REL T 9x is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet; KEF KC92 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. |
| Cabinet size | depends | KEF KC92 is about 30% 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 | REL T 9x carries 3 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 | REL T 9x costs less - $1,699 against $1,999, about 15% less. |
A REL T 9x B KEF KC92
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 KC92 measures better, REL T 9x costs about 15% 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, REL T 9x will hit harder for the money; if it is mainly for music in a normal-sized room, KEF KC92 is usually the easier one to make sound right. If placement is the constraint - a corner, behind a sofa, under a desk - KEF KC92 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.