In this review, we will be comparing Theatrus TS15 Passive 15" Subwoofer and DB4S, two Powered Subwoofer speakers from Aperion and Bowers Wilkins. 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 Aperion Theatrus TS15 Passive 15" Subwoofer and B&W DB4S 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 Aperion Theatrus TS15 Passive 15" Subwooferand B&W DB4S have a single woofer setup however the Aperion Theatrus TS15 Passive 15" Subwoofer's woofer is 15-inch whereas the B&W DB4S features a 10-inch woofer.
Frequency Response
Theatrus TS15 Passive 15" Subwoofer has a frequency range of 18-400 Hz whereas DB4S has a frequency range of 10-350 Hz. With a minimum frequency of 10Hz, the DB4S can go significantly deeper on the low side and provide stronger bass compared to the Theatrus TS15 Passive 15" Subwoofer's min frequency of 18Hz.
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
Aperion Theatrus TS15 Passive 15" Subwoofer
High Frequency
Subwoofer Speakers
Aperion Theatrus TS15 Passive 15" Subwoofer
Cabinet Type
Both Aperion Theatrus TS15 Passive 15" Subwoofer and B&W DB4S 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 Aperion Theatrus TS15 Passive 15" Subwoofer's and B&W DB4S's external dimensions. Aperion Theatrus TS15 Passive 15" Subwoofer has external dimensions of 500.4 x 500.4 x 401.3mm (19.7 x 19.7 x 15.8inch) whereas B&W DB4S has external dimensions of 375.0 x 362.0 x 434.0mm (14-3/4 x 14-1/4 x 17-1/16inch).
B&W DB4S is 138.4mm narrower and 125.4mm shorter than Aperion Theatrus TS15 Passive 15" Subwoofer but it is also 32.7mm deeper.
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.
Aperion Theatrus TS15 Passive 15" Subwoofer needs about 28% more floor or shelf area. B&W DB4S is 33mm deeper, so it stands that much further out from the wall. Aperion Theatrus TS15 Passive 15" Subwoofer is 125mm 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 Aperion Theatrus TS15 Passive 15" Subwoofer is approximately 2008.1cm2 / 311.3inch2 and base area of the B&W DB4S is approximately 1571.1cm2 / 243.5inch2. The Theatrus TS15 Passive 15" Subwoofer requires 28% more surface area than the DB4S 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 Aperion Theatrus TS15 Passive 15" Subwoofer weighs 35.02kg / 77lbs and the B&W DB4S weighs 26.05kg / 57.3lbs. This makes the Theatrus TS15 Passive 15" Subwoofer 34% heavier than the DB4S.
Here is a comparison of how Theatrus TS15 Passive 15" Subwoofer and DB4S's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
Aperion Theatrus TS15 Passive 15" Subwoofer
 Woofer Size |
15 inches
vs
10 inches
|
Larger woofer |
 High Frequency Response |
400 Hz
vs
350 Hz
|
Generates higher frequency |
 Price per pair* |
1449USD
vs
2199USD
|
costs less (*prices may change depending on the seller, location and time) |
| Low Frequency Response |
10 Hz
vs
18 Hz
|
Generates deeper bass |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
 Height |
375mm
vs
500mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1571cm2
vs
2008cm2
|
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.
Aperion Theatrus TS15 Passive 15" Subwoofer needs about 28% more floor area. B&W DB4S stands 33mm further into the room. Aperion Theatrus TS15 Passive 15" Subwoofer is 125mm taller.
| General |
Aperion Theatrus TS15 Passive 15" Subwoofer |
Bowers & Wilkins DB4S |
| Brand |
Aperion |
Bowers Wilkins |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Sensitivity |
88 dB |
n/a |
| Impedance |
4 ohms |
n/a |
| Frequency Response |
18-400 Hz |
10-350 Hz |
Amplifier |
|
|
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
15" |
10" |
| Woofer Composition |
|
Aerofoil |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
500.4mm (19.7") |
375.0mm (14.8") |
| Width |
500.4mm (19.7") |
362.0mm (14.3") |
| Depth |
401.3mm (15.8") |
434.0mm (17.1") |
| Weight |
35.02kg (77lbs) |
26.05kg (57.3lbs) |
| Enclosure |
Acoustic Suspension |
Acoustic Suspension |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
|
2 Years |
| Labor Warranty |
|
2 Years |
Two quite different sizes of subwoofer. Room volume decides this more than anything else on the page: a big driver in a small room is wasted, and a small one in a large room is worked to death.
| Area | Better | Why |
|---|
| Bass depth | B | B&W DB4S goes deeper - 10Hz against 18Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Driver area | A | Aperion Theatrus TS15 Passive 15" Subwoofer moves more air: 15" against 10" 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 | evenly matched | Both are sealed designs, so they roll off in much the same way. |
| Cabinet size | depends | B&W DB4S is about 41% 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 | Aperion Theatrus TS15 Passive 15" Subwoofer costs less - $1,449 against $2,199, about 34% less. |
A Aperion Theatrus TS15 Passive 15" Subwoofer B B&W DB4S
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. If placement is the constraint - a corner, behind a sofa, under a desk - B&W DB4S 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.