In this review, we will be comparing TZero MKIII and ProSub 1000, two Powered Subwoofer speakers from REL and Definitive Technology. 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 Definitive ProSub 1000 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 Definitive ProSub 1000 have a single woofer setup however the REL TZero MKIII's woofer is 6.5-inch whereas the Definitive ProSub 1000 features a 10-inch woofer.
Frequency Response
TZero MKIII has a frequency range of 37-120 Hz whereas ProSub 1000 has a frequency range of 18-150 Hz. With a minimum frequency of 18Hz, the ProSub 1000 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 Definitive ProSub 1000's external dimensions. REL TZero MKIII has external dimensions of 242.9 x 217.5 x 295.3mm () whereas Definitive ProSub 1000 has external dimensions of 366.0 x 307.0 x 486.0mm (14-3/8 x 12-1/16 x 19-1/8inch).
Definitive ProSub 1000 is clearly the larger of the two speakers. Its body is 89.5mm wider, 123.1mm taller and 190.7mm 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 Definitive ProSub 1000 is approximately 1492.0cm2 / 231.3inch2. The TZero MKIII requires 57% less surface area than the ProSub 1000 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 Definitive ProSub 1000 weighs 14.09kg / 31lbs. This makes the ProSub 1000 107% heavier than the TZero MKIII.
Here is a comparison of how TZero MKIII and ProSub 1000's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Height |
242mm
vs
366mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
642cm2
vs
1492cm2
|
Takes less floor space |
 Woofer Size |
10 inches
vs
6.5 inches
|
Larger woofer |
| Low Frequency Response |
18 Hz
vs
37 Hz
|
Generates deeper bass |
 High Frequency Response |
150 Hz
vs
120 Hz
|
Generates higher frequency |
 Price per pair* |
499USD
vs
599USD
|
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.
Definitive ProSub 1000 needs about 132% more floor area. Definitive ProSub 1000 stands 191mm further into the room. Definitive ProSub 1000 is 123mm taller.
| General |
REL TZero MKIII |
Definitive Technology ProSub 1000 |
| Brand |
REL |
Definitive Technology |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
37-120 Hz |
18-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
100-watt RMS |
300-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
6.5" |
10" |
| Woofer Composition |
|
Polymer |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-150 Hz and 80 Hz |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
242.9mm (9.6") |
366.0mm (14.4") |
| Width |
217.5mm (8.6") |
307.0mm (12.1") |
| Depth |
295.3mm (11.6") |
486.0mm (19.1") |
| Weight |
6.80kg (15lbs) |
14.09kg (31lbs) |
| Enclosure |
|
Passive Radiator |
| 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 passive radiator 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 | Definitive ProSub 1000 goes deeper - 18Hz against 37Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | B | Definitive ProSub 1000 has the bigger amplifier - 300W against 100W RMS, about 4.8dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | Definitive ProSub 1000 moves more air: 10" against 6.5" is 2.37x the cone area, not the 1.54x 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; Definitive ProSub 1000 is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet. 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 71% 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 | B | Definitive ProSub 1000 costs less - $499 against $599, about 17% less. |
A REL TZero MKIII B Definitive ProSub 1000
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?
Definitive ProSub 1000 is the easier recommendation: it leads on most of the measured areas and costs less. Take REL TZero MKIII if one of the "depends" rows describes your room. Films or music? If this is mainly a home cinema, Definitive ProSub 1000 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. If placement is the constraint - a corner, behind a sofa, under a desk - REL TZero MKIII 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.