In this review, we will be comparing Gravis I and Gravis II, two Powered Subwoofer speakers by Sonus faber. 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 I and Sonus faber Gravis II 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 Iand Sonus faber Gravis II have a single woofer setup however the Sonus faber Gravis I's woofer is 8-inch whereas the Sonus faber Gravis II features a 10-inch woofer.
Frequency Response
Gravis I has a frequency range of 30-120 Hz whereas Gravis II has a frequency range of 25-120 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 Gravis I'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 I has a Acoustic Suspension type cabinet. 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. On the other hand the Sonus faber Gravis II have Passive Radiator type enclosure. 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.
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 I's and Sonus faber Gravis II's external dimensions. Sonus faber Gravis I has external dimensions of 337.0 x 286.0 x 340.0mm (13-1/4inch x 11-1/4inch x 13-3/8inch) whereas 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).
Sonus faber Gravis II is clearly the larger of the two speakers. Its body is 72mm wider, 70mm taller and 95mm deeper than Sonus faber Gravis I.
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.
Sonus faber Gravis II needs about 60% more floor or shelf area. Sonus faber Gravis II is 95mm deeper, so it stands that much further out from the wall. Sonus faber Gravis II is 70mm 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 I is approximately 972.4cm2 / 150.7inch2 and base area of the Sonus faber Gravis II is approximately 1557.3cm2 / 241.4inch2. The Gravis I requires 38% less surface area than the Gravis II 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 I weighs 14.55kg / 32lbs and the Sonus faber Gravis II weighs 21.50kg / 47.3lbs. This makes the Gravis II 48% heavier than the Gravis I.
Here is a comparison of how Gravis I and Gravis II'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 I?
Here are the items that are included inside the box of Gravis I:
- Powered subwoofer
- 6-feet AC power cord
- 33-feet Speakon cable
- Owners Manual
- Environmental Information
What's in the Box of Sonus faber Gravis II?
Here are the items that come with the Gravis II:
- Powered subwoofer
- Grille
- 6-feet AC power cord
- 33-feet Speakon cable
- Owners Manual
- Environmental Information
 Height |
337mm
vs
407mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
972cm2
vs
1557cm2
|
Takes less floor space |
 Price per pair* |
999USD
vs
1499USD
|
costs less (*prices may change depending on the seller, location and time) |
 Woofer Size |
10 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
25 Hz
vs
30 Hz
|
Generates deeper bass |
 Passive Radiator |
2 x 10-inch
vs
None
|
Increases the bass performance |
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.
Sonus faber Gravis II needs about 60% more floor area. Sonus faber Gravis II stands 95mm further into the room. Sonus faber Gravis II is 70mm taller.
| General |
Sonus faber Gravis I |
Sonus faber Gravis II |
| Brand |
Sonus faber |
Sonus faber |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
150 watts |
350 watts |
| Frequency Response |
30-120 Hz |
25-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
150-watt RMS |
350-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
10" |
| Woofer Composition |
Treated Paper |
Treated Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
bottom |
front |
Physical Specs |
|
|
| Height |
337.0mm (13.3") |
407.0mm (16") |
| Width |
286.0mm (11.3") |
358.0mm (14.1") |
| Depth |
340.0mm (13.4") |
435.0mm (17.1") |
| Weight |
14.55kg (32lbs) |
21.50kg (47.3lbs) |
| Enclosure |
Acoustic Suspension |
Passive Radiator |
| Available Colors |
Piano Black,Matte White |
Piano Black,Matte White |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Yr/3 Yr registered |
2 Yr/3 Yr registered |
| Labor Warranty |
2 Yr/3 Yr registered |
2 Yr/3 Yr registered |
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 | 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 | B | Sonus faber Gravis II has the bigger amplifier - 350W against 150W RMS, about 3.7dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | Sonus faber Gravis II 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 | Sonus faber Gravis I is sealed - a sealed box rolls off gently and is usually the easier one to integrate in a small or awkward room; Sonus faber Gravis II 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. |
| Driver placement | depends | Sonus faber Gravis I fires down and Sonus faber Gravis II fires front/down. 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 I is about 48% 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 | Sonus faber Gravis I costs less - $999 against $1,499, about 33% less. |
A Sonus faber Gravis I B Sonus faber Gravis II
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: Sonus faber Gravis II measures better, Sonus faber Gravis I costs about 33% 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, Sonus faber Gravis II will hit harder for the money; if it is mainly for music in a normal-sized room, Sonus faber Gravis I is usually the easier one to make sound right. If placement is the constraint - a corner, behind a sofa, under a desk - Sonus faber Gravis I 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.