In this review, we will be comparing RP-1400CSW and Gravis II, two Powered Subwoofer speakers from Klipsch and 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 Klipsch RP-1400CSW 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 Klipsch RP-1400CSWand Sonus faber Gravis II have a single woofer setup however the Klipsch RP-1400CSW's woofer is 14-inch whereas the Sonus faber Gravis II features a 10-inch woofer.
Frequency Response
RP-1400CSW has a frequency range of 15-180 Hz whereas Gravis II has a frequency range of 25-120 Hz. With a minimum frequency of 15Hz, the RP-1400CSW can go significantly deeper on the low side and provide stronger bass compared to the Gravis II's min frequency of 25Hz.
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 Klipsch RP-1400CSW 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 Klipsch RP-1400CSW's and Sonus faber Gravis II's external dimensions. Klipsch RP-1400CSW has external dimensions of 444.0 x 421.6 x 421.6mm (17.48inch x 16.6inch x 16.6inch) 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 63.6mm narrower and 37mm shorter than Klipsch RP-1400CSW but it is also 13.4mm deeper.
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 Klipsch RP-1400CSW is approximately 1777.5cm2 / 275.5inch2 and base area of the Sonus faber Gravis II is approximately 1557.3cm2 / 241.4inch2. The RP-1400CSW requires 14% more surface area than the Gravis II 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 Klipsch RP-1400CSW weighs 27.08kg / 59.6lbs and the Sonus faber Gravis II weighs 21.50kg / 47.3lbs. This makes the RP-1400CSW 26% heavier than the Gravis II.
Here is a comparison of how RP-1400CSW and Gravis II's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Woofer Size |
14 inches
vs
10 inches
|
Larger woofer |
| Low Frequency Response |
15 Hz
vs
25 Hz
|
Generates deeper bass |
 High Frequency Response |
180 Hz
vs
120 Hz
|
Generates higher frequency |
 Price per pair* |
1100USD
vs
1499USD
|
costs less (*prices may change depending on the seller, location and time) |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
 Passive Radiator |
2 x 10-inch
vs
None
|
Increases the bass performance |
 Height |
407mm
vs
444mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1557cm2
vs
1777cm2
|
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.
Klipsch RP-1400CSW needs about 14% more floor area. Klipsch RP-1400CSW is 37mm taller.
| General |
Klipsch Reference Premiere RP-1400CSW |
Sonus faber Gravis II |
| Brand |
Klipsch |
Sonus faber |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
500 watts |
350 watts |
| Frequency Response |
15-180 Hz |
25-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
500-watt RMS |
350-watt RMS |
| Watts Peak (Max) |
1000-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
14" |
10" |
| Woofer Composition |
Cerametallic |
Treated Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
444.0mm (17.5") |
407.0mm (16") |
| Width |
421.6mm (16.6") |
358.0mm (14.1") |
| Depth |
421.6mm (16.6") |
435.0mm (17.1") |
| Weight |
27.08kg (59.6lbs) |
21.50kg (47.3lbs) |
| Enclosure |
Acoustic Suspension |
Passive Radiator |
| Finish |
MDF with Vinyl |
n/a |
| Available Colors |
Ebony |
Piano Black,Matte White |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
|
2 Yr/3 Yr registered |
| Labor Warranty |
|
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 | A | Klipsch RP-1400CSW goes deeper - 15Hz against 25Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | A | Klipsch RP-1400CSW has the bigger amplifier - 500W against 350W RMS, about 1.5dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | Klipsch RP-1400CSW moves more air: 14" against 10" is 1.96x the cone area, not the 1.4x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | Klipsch RP-1400CSW 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. |
| Speaker-level inputs | B | 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. |
| Wireless option | depends | Only Klipsch RP-1400CSW offers a wireless link (as a paid option). It decides where the sub can go if you cannot run a cable, and is worth nothing if you can. |
| Driver placement | depends | Klipsch RP-1400CSW fires front 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 II is about 20% 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 | Klipsch RP-1400CSW costs less - $1,100 against $1,499, about 27% less. |
A Klipsch RP-1400CSW 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?
Klipsch RP-1400CSW is the easier recommendation: it leads on most of the measured areas and costs less. Take Sonus faber Gravis II if one of the "depends" rows describes your room. 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, Klipsch RP-1400CSW is usually the easier one to make sound right. 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.
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.