In this review, we will be comparing TZero MKIII and SW-15, two Powered Subwoofer speakers from REL and Wharfedale. 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 TZero MKIII and Wharfedale SW-15 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 TZero MKIIIand Wharfedale SW-15 have a single woofer setup however the REL TZero MKIII's woofer is 6.5-inch whereas the Wharfedale SW-15 features a 15-inch woofer.
Frequency Response
TZero MKIII has a frequency range of 37-120 Hz whereas SW-15 has a frequency range of 30-120 Hz. With a minimum frequency of 30Hz, the SW-15 can go significantly deeper on the low side and provide stronger bass compared to the TZero MKIII's min frequency of 37Hz.
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 TZero MKIII's and Wharfedale SW-15's external dimensions. REL TZero MKIII has external dimensions of 242.9 x 217.5 x 295.3mm () whereas Wharfedale SW-15 has external dimensions of 570.0 x 493.0 x 615.0mm (22-7/16inch x 19-3/8inch x 24-3/16inch).
Wharfedale SW-15 is clearly the larger of the two speakers. Its body is 275.5mm wider, 327.1mm taller and 319.7mm deeper than REL TZero MKIII.
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 TZero MKIII is approximately 642.3cm2 / 99.6inch2 and base area of the Wharfedale SW-15 is approximately 3032.0cm2 / 470.0inch2. The TZero MKIII requires 79% less surface area than the SW-15 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 TZero MKIII weighs 6.80kg / 15lbs and the Wharfedale SW-15 weighs 31.57kg / 69.5lbs. This makes the SW-15 364% heavier than the TZero MKIII.
Here is a comparison of how TZero MKIII and SW-15's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Height |
242mm
vs
570mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
642cm2
vs
3032cm2
|
Takes less floor space |
 Price per pair* |
599USD
vs
1199USD
|
costs less (*prices may change depending on the seller, location and time) |
 Woofer Size |
15 inches
vs
6.5 inches
|
Larger woofer |
| Low Frequency Response |
30 Hz
vs
37 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.
Wharfedale SW-15 needs about 372% more floor area. Wharfedale SW-15 stands 320mm further into the room. Wharfedale SW-15 is 327mm taller.
| General |
REL TZero MKIII |
Wharfedale SW-15 |
| Brand |
REL |
Wharfedale |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
37-120 Hz |
30-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
100-watt RMS |
400-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
6.5" |
15" |
| Woofer Composition |
|
Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
242.9mm (9.6") |
570.0mm (22.4") |
| Width |
217.5mm (8.6") |
493.0mm (19.4") |
| Depth |
295.3mm (11.6") |
615.0mm (24.2") |
| Weight |
6.80kg (15lbs) |
31.57kg (69.5lbs) |
| Enclosure |
|
Bass Reflex |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
3 Years |
3 Years |
| Labor Warranty |
3 Years |
3 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 | Wharfedale SW-15 goes deeper - 30Hz against 37Hz. A real difference, though most music has little content below 37Hz. |
| Amplifier power | B | Wharfedale SW-15 has the bigger amplifier - 400W against 100W RMS, about 6dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | Wharfedale SW-15 moves more air: 15" against 6.5" is 5.33x the cone area, not the 2.31x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | REL TZero MKIII is sealed - a sealed box rolls off gently and is usually the easier one to integrate in a small or awkward room; Wharfedale SW-15 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 TZero MKIII is about 91% 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. |
| Price | A | REL TZero MKIII costs less - $599 against $1,199, about 50% less. |
A REL TZero MKIII B Wharfedale SW-15
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: Wharfedale SW-15 measures better, REL TZero MKIII costs about 50% 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, Wharfedale SW-15 will hit harder for the money; if it is mainly for music in a normal-sized room, REL TZero MKIII 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 $599 each, two REL TZero MKIII cost about $1,198 against $1,199 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.