In this review, we will be comparing Alpha S8 and DB4S, two Powered Subwoofer speakers from PSB 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 PSB Alpha S8 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 PSB Alpha S8and B&W DB4S have a single woofer setup however the PSB Alpha S8's woofer is 8-inch whereas the B&W DB4S features a 10-inch woofer.
Frequency Response
Alpha S8 has a frequency range of 35-150 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 Alpha S8's min frequency of 35Hz.
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
Cabinet Type
The PSB Alpha S8 has a Bass Reflex type cabinet. Bass Reflex type subwoofers (aka Ported, Vented or Reflex Port) have enclosures that uses a port, hole or vent cut into the cabinet. Ported designs are generally more efficient than the Sealed designs. On the other hand the B&W DB4S have Acoustic Suspension type enclosure. 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 PSB Alpha S8's and B&W DB4S's external dimensions. PSB Alpha S8 has external dimensions of 318.0 x 293.0 x 413.0mm (12-1/2 x 11-1/2 x 16-1/4inch) 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 clearly the larger of the two speakers. Its body is 69mm wider, 57mm taller and 21mm deeper than PSB Alpha S8.
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 PSB Alpha S8 is approximately 1210.1cm2 / 187.6inch2 and base area of the B&W DB4S is approximately 1571.1cm2 / 243.5inch2. The Alpha S8 requires 23% less surface area than the DB4S 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 PSB Alpha S8 weighs 9.55kg / 21lbs and the B&W DB4S weighs 26.05kg / 57.3lbs. This makes the DB4S 173% heavier than the Alpha S8.
Here is a comparison of how Alpha S8 and DB4S's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of PSB Alpha S8?
Here are the items that are included inside the box of Alpha S8:
- Powered subwoofer
- Grille
- 5-feet AC power cord
- 4 Rubber feet
- 4 Spike feet
- 4 Hex-nuts
- Quick Start Guide
- Important Safety Instructions
- Warranty Information
What's in the Box of B&W DB4S?
Here are the items that come with the DB4S:
- Powered subwoofer
- Grille
- 6.5-feet AC power cord
- 4 Decoupling feet
- 4 Rubber feet
- 4 Spike feet
- 4 Lock-nuts
- Cleaning cloth
- Quickstart Guide
- Bowers & Wilkins brochure
- Warranty Information
- Cleaning cloth instructions
 Height |
318mm
vs
375mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1210cm2
vs
1571cm2
|
Takes less floor space |
 Price per pair* |
549USD
vs
2199USD
|
costs less (*prices may change depending on the seller, location and time) |
 Woofer Size |
10 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
10 Hz
vs
35 Hz
|
Generates deeper bass |
 High Frequency Response |
350 Hz
vs
150 Hz
|
Generates higher frequency |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
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.
B&W DB4S needs about 30% more floor area. B&W DB4S stands 21mm further into the room. B&W DB4S is 57mm taller.
| General |
PSB Alpha S8 |
Bowers & Wilkins DB4S |
| Brand |
PSB |
Bowers Wilkins |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
150 watts |
1000 watts |
| Frequency Response |
35-150 Hz |
10-350 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
150-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
10" |
| Woofer Composition |
Polypropylene |
Aerofoil |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
318.0mm (12.5") |
375.0mm (14.8") |
| Width |
293.0mm (11.5") |
362.0mm (14.3") |
| Depth |
413.0mm (16.3") |
434.0mm (17.1") |
| Weight |
9.55kg (21lbs) |
26.05kg (57.3lbs) |
| Enclosure |
Bass Reflex |
Acoustic Suspension |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
1 Year |
2 Years |
| Labor Warranty |
1 Year |
2 Years |
A ported 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 | B&W DB4S goes deeper - 10Hz against 35Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | B | B&W DB4S has the bigger amplifier - 1000W against 150W RMS, about 8.2dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | B&W DB4S moves more air: 10" against 8" is 1.56x the cone area, not the 1.25x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | PSB Alpha S8 is ported - a ported box gives more output low down for its size, at the cost of a steeper roll-off below tuning; B&W DB4S 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 | PSB Alpha S8 is about 35% 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 | B | B&W DB4S carries 2 years on parts against 1 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | A | PSB Alpha S8 costs less - $549 against $2,199, about 75% less. |
A PSB Alpha S8 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?
The usual trade-off: B&W DB4S measures better, PSB Alpha S8 costs about 75% 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, PSB Alpha S8 will hit harder for the money; if it is mainly for music in a normal-sized room, B&W DB4S 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 $549 each, two PSB Alpha S8 cost about $1,098 against $2,199 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.