In this review, we will be comparing T 5x and SPL-120, two Powered Subwoofer speakers from REL and Klipsch. 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 5x and Klipsch SPL-120 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 REL T 5xand Klipsch SPL-120 have a single woofer setup however the REL T 5x's woofer is 8-inch whereas the Klipsch SPL-120 features a 12-inch woofer.
Frequency Response
T 5x has a frequency range of 32-120 Hz whereas SPL-120 has a frequency range of 24-125 Hz. With a minimum frequency of 24Hz, the SPL-120 can go significantly deeper on the low side and provide stronger bass compared to the T 5x's min frequency of 32Hz.
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 5x's and Klipsch SPL-120's external dimensions. REL T 5x has external dimensions of 312.7 x 300.0 x 360.4mm () whereas Klipsch SPL-120 has external dimensions of 450.0 x 375.0 x 540.0mm (17-11/16 x 14-3/4 x 21-1/4inch).
Klipsch SPL-120 is clearly the larger of the two speakers. Its body is 75mm wider, 137.3mm taller and 179.6mm deeper than REL T 5x.
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 5x is approximately 1081.2cm2 / 167.6inch2 and base area of the Klipsch SPL-120 is approximately 2025.0cm2 / 313.9inch2. The T 5x requires 47% less surface area than the SPL-120 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 REL T 5x weighs 14.29kg / 31.4lbs and the Klipsch SPL-120 weighs 20.45kg / 45lbs. This makes the SPL-120 43% heavier than the T 5x.
Here is a comparison of how T 5x and SPL-120's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Height |
312mm
vs
450mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1081cm2
vs
2025cm2
|
Takes less floor space |
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
24 Hz
vs
32 Hz
|
Generates deeper bass |
 High Frequency Response |
125 Hz
vs
120 Hz
|
Generates higher frequency |
 Price per pair* |
499USD
vs
799USD
|
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.
Klipsch SPL-120 needs about 87% more floor area. Klipsch SPL-120 stands 180mm further into the room. Klipsch SPL-120 is 137mm taller.
| General |
REL T 5x |
Klipsch SPL-120 |
| Brand |
REL |
Klipsch |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
32-120 Hz |
24-125 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
125-watt RMS |
300-watt RMS |
| Watts Peak (Max) |
n/a |
600-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
12" |
| Woofer Composition |
|
Cerametallic |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
312.7mm (12.3") |
450.0mm (17.7") |
| Width |
300.0mm (11.8") |
375.0mm (14.8") |
| Depth |
360.4mm (14.2") |
540.0mm (21.3") |
| Weight |
14.29kg (31.4lbs) |
20.45kg (45lbs) |
| Enclosure |
|
Bass Reflex |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
2 Years |
| Labor Warranty |
3 Years |
2 Years |
A sealed subwoofer against a ported 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 | Klipsch SPL-120 goes deeper - 24Hz against 32Hz. That gap covers the lowest notes of a five-string bass and a concert bass drum. |
| Amplifier power | B | Klipsch SPL-120 has the bigger amplifier - 300W against 125W RMS, about 3.8dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | Klipsch SPL-120 moves more air: 12" against 8" is 2.25x the cone area, not the 1.5x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | REL T 5x is sealed - a sealed box rolls off gently and is usually the easier one to integrate in a small or awkward room; Klipsch SPL-120 is ported - a ported box gives more output low down for its size, at the cost of a steeper roll-off below tuning. 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 | REL T 5x is about 63% 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 5x 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 | B | Klipsch SPL-120 costs less - $499 against $799, about 38% less. |
A REL T 5x B Klipsch SPL-120
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?
Klipsch SPL-120 is the easier recommendation: it leads on most of the measured areas and costs less. Take REL T 5x if one of the "depends" rows describes your room. Films or music? If this is mainly a home cinema, Klipsch SPL-120 will hit harder for the money; if it is mainly for music in a normal-sized room, REL T 5x is usually the easier one to make sound right. 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 $499 each, two Klipsch SPL-120 cost about $998 against $799 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.