In this review, we will be comparing Gravis II and SW-15, two Powered Subwoofer speakers from Sonus faber 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 Sonus faber Gravis II 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 Sonus faber Gravis IIand Wharfedale SW-15 have a single woofer setup however the Sonus faber Gravis II's woofer is 10-inch whereas the Wharfedale SW-15 features a 15-inch woofer.
Frequency Response
Gravis II has a frequency range of 25-120 Hz whereas SW-15 has a frequency range of 30-120 Hz. With a minimum frequency of 25Hz, the Gravis II can go significantly deeper on the low side and provide stronger bass compared to the SW-15's min frequency of 30Hz.
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 Sonus faber Gravis II has a Passive Radiator type cabinet. Passive Radiator type subwoofers sports a non-powered cone that moves in response to the main woofer to move air out in order to generate stronger bass in a smaller body compared to ported or sealed designs. On the other hand the Wharfedale SW-15 have Bass Reflex type enclosure. 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.
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 Sonus faber Gravis II's and Wharfedale SW-15's external dimensions. Sonus faber Gravis II has external dimensions of 407.0 x 358.0 x 435.0mm (16inch x 14-1/16inch x 17-1/8inch) 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 135mm wider, 163mm taller and 180mm deeper than Sonus faber Gravis II.
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.
Wharfedale SW-15 needs about 95% more floor or shelf area. Wharfedale SW-15 is 180mm deeper, so it stands that much further out from the wall. Wharfedale SW-15 is 163mm 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 Sonus faber Gravis II is approximately 1557.3cm2 / 241.4inch2 and base area of the Wharfedale SW-15 is approximately 3032.0cm2 / 470.0inch2. The Gravis II requires 49% 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 Sonus faber Gravis II weighs 21.50kg / 47.3lbs and the Wharfedale SW-15 weighs 31.57kg / 69.5lbs. This makes the SW-15 47% heavier than the Gravis II.
Here is a comparison of how Gravis II and SW-15's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of Sonus faber Gravis II?
Here are the items that are included inside the box of Gravis II:
- Powered subwoofer
- Grille
- 6-feet AC power cord
- 33-feet Speakon cable
- Owners Manual
- Environmental Information
What's in the Box of Wharfedale SW-15?
Here are the items that come with the SW-15:
- Powered subwoofer
- Grille
- 6.5-feet AC power cord
- User-feets Manual
 Low Frequency Response |
25 Hz
vs
30 Hz
|
Generates deeper bass |
 Port Position |
Front
vs
Rear
|
Gives more flexibility placing close to walls |
 Passive Radiator |
2 x 10-inch
vs
None
|
Increases the bass performance |
 Height |
407mm
vs
570mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1557cm2
vs
3032cm2
|
Takes less floor space |
| Woofer Size |
15 inches
vs
10 inches
|
Larger woofer |
 Price per pair* |
1199USD
vs
1499USD
|
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.
Wharfedale SW-15 needs about 95% more floor area. Wharfedale SW-15 stands 180mm further into the room. Wharfedale SW-15 is 163mm taller.
| General |
Sonus faber Gravis II |
Wharfedale SW-15 |
| Brand |
Sonus faber |
Wharfedale |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
350 watts |
400 watts |
| Frequency Response |
25-120 Hz |
30-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
350-watt RMS |
400-watt RMS |
| Watts Peak (Max) |
n/a |
850-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
10" |
15" |
| Woofer Composition |
Treated Paper |
Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
rear |
Physical Specs |
|
|
| Height |
407.0mm (16") |
570.0mm (22.4") |
| Width |
358.0mm (14.1") |
493.0mm (19.4") |
| Depth |
435.0mm (17.1") |
615.0mm (24.2") |
| Weight |
21.50kg (47.3lbs) |
31.57kg (69.5lbs) |
| Enclosure |
Passive Radiator |
Bass Reflex |
| Available Colors |
Piano Black,Matte White |
n/a |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Yr/3 Yr registered |
3 Years |
| Labor Warranty |
2 Yr/3 Yr registered |
3 Years |
A passive radiator 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 | A | Sonus faber Gravis II goes deeper - 25Hz against 30Hz. That gap covers the lowest notes of a five-string bass and a concert bass drum. |
| Amplifier power | evenly matched | Much the same amplifier (350W vs 400W RMS) - under 1dB apart. |
| Driver area | B | Wharfedale SW-15 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 | depends | Sonus faber Gravis II is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet; 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. |
| Speaker-level inputs | A | Sonus faber Gravis II takes a speaker-level connection as well as line level. That is what lets it work with an integrated amplifier or a vintage receiver that has no subwoofer output at all. |
| Driver placement | depends | Sonus faber Gravis II fires front/down and Wharfedale SW-15 fires front. A down-firing driver is more forgiving of a grille-less look and of a hard floor; a front-firing one is the safer choice on a thick carpet or a suspended timber floor. |
| Cabinet size | depends | Sonus faber Gravis II 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 | B | Wharfedale SW-15 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 | Wharfedale SW-15 costs less - $1,199 against $1,499, about 20% less. |
A Sonus faber Gravis II 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?
Neither runs away with it - they trade advantages. Let your room size and where the box can actually stand settle it. Check your amplifier first: if it has no subwoofer or preamp output, Sonus faber Gravis II is the only one of these two you can connect at all. If placement is the constraint - a corner, behind a sofa, under a desk - Sonus faber Gravis II 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.