In this review, we will be comparing Gravis I and R-121SW, two Powered Subwoofer speakers from Sonus Faber and Klipsch. 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 Klipsch R-121SW first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the Sonus faber Gravis I and Klipsch R-121SW compare and hopefully end up with enough arguments to decide which one of these subwoofers is the better choice for you.
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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 Klipsch R-121SW have a single woofer setup however the Sonus faber Gravis I's woofer is 8-inch whereas the Klipsch R-121SW features a 12-inch woofer.
Frequency Response
Gravis I has a frequency range of 30-120 Hz whereas R-121SW has a frequency range of 28-120 Hz. With a minimum frequency of 28Hz, the R-121SW can go slightly deeper then 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 Klipsch R-121SW 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.
Klipsch R-121SW Port
Physical Specs
Size of a speaker can sometimes become 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 Klipsch R-121SW'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 Klipsch R-121SW has external dimensions of 423.0 x 407.0 x 532.0mm ( 16-5/8inch x 16inch x 20-15/16inch ) .
Klipsch R-121SW is clearly the larger of the two speakers. Its body is 121mm wider, 86mm taller and 192mm deeper than Sonus faber Gravis I.
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 Klipsch R-121SW is approximately 2165.2cm2 / 335.6inch2. The Gravis I requires 55% less surface area than the R-121SW 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 Klipsch R-121SW weighs 16.00kg / 35.2lbs. This makes the R-121SW 10% heavier than the Gravis I.
Here is a comparison of how Gravis I and R-121SW'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 subwoofer6-feet AC power cord33-feet Speakon cableOwners ManualEnvironmental Information
What's in the Box of Klipsch R-121SW?
Here are the items that come with the R-121SW:
Powered subwooferGrille6.5-feet AC power cordUser ManualImportant Safety InstructionsWarranty Information
 Height |
337mm
vs
423mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
972cm2
vs
2165cm2
|
Takes less floor space |
 Driver Setup |
1-way
vs
-way
|
Have a dedicated mid-range driver |
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
28 Hz
vs
30 Hz
|
Generates deeper bass |
 Price per pair* |
599USD
vs
999USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Sonus faber Gravis I |
Klipsch Reference R-121SW |
| Brand |
Sonus Faber |
Klipsch |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
150 watts |
200 watts |
| Frequency Response |
30-120 Hz |
28-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
150-watt RMS |
200-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
12" |
| Woofer Composition |
Treated Paper |
Spun-Copper TCP |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
bottom |
front |
Physical Specs |
|
|
| Height |
337.0mm (13.3") |
423.0mm (16.7") |
| Width |
286.0mm (11.3") |
407.0mm (16") |
| Depth |
340.0mm (13.4") |
532.0mm (20.9") |
| Weight |
14.55kg (32lbs) |
16.00kg (35.2lbs) |
| Enclosure |
Acoustic Suspension |
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 |
2 Years |
| Labor Warranty |
2 Yr/3 Yr registered |
2 Years |