In this review, we will be comparing Grotto 12 and R-121SW, two Powered Subwoofer speakers from MartinLogan 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 MartinLogan Grotto 12 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 MartinLogan Grotto 12 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.MartinLogan Grotto 12and Klipsch R-121SW have the same driver set up: Both subwoofers have 1 x 12" drivers.
Frequency Response
Grotto 12 has a frequency range of 22-120 Hz whereas R-121SW has a frequency range of 28-120 Hz. With a minimum frequency of 22Hz, the Grotto 12 can go significantly deeper on the low side and provide stronger bass compared to the R-121SW's min frequency of 28Hz.
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 MartinLogan Grotto 12 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 MartinLogan Grotto 12's and Klipsch R-121SW's external dimensions. MartinLogan Grotto 12 has external dimensions of 452.0 x 454.0 x 454.0mm ( 17-13/16 x 17-7/8 x 17-7/8inch) 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 47mm narrower and 29mm shorter than MartinLogan Grotto 12 but it is also 78mm 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 MartinLogan Grotto 12 is approximately 2061.2cm2 / 319.5inch2 and base area of the Klipsch R-121SW is approximately 2165.2cm2 / 335.6inch2. The Grotto 12 requires 5% 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 MartinLogan Grotto 12 weighs 37.40kg / 82.3lbs and the Klipsch R-121SW weighs 16.00kg / 35.2lbs. This makes the Grotto 12 134% heavier than the R-121SW.
Here is a comparison of how Grotto 12 and R-121SW's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Low Frequency Response |
22 Hz
vs
28 Hz
|
Generates deeper bass |
 Passive Radiator |
2 x 12-inch
vs
None
|
Increases the bass performance |
 Base Surface Area |
2061cm2
vs
2165cm2
|
Takes less floor space |
 Height |
423mm
vs
452mm
|
Easier to fit in smaller spaces |
 Price per pair* |
599USD
vs
2300USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
MartinLogan Grotto 12 |
Klipsch Reference R-121SW |
| Brand |
MartinLogan |
Klipsch |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
1000 watts |
200 watts |
| Frequency Response |
22-120 Hz |
28-120 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
1000-watt RMS |
200-watt RMS |
| Watts Peak (Max) |
2000-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
12" |
| Woofer Composition |
Aluminium |
Spun-Copper TCP |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
35–120Hz |
n/a |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
452.0mm (17.8") |
423.0mm (16.7") |
| Width |
454.0mm (17.9") |
407.0mm (16") |
| Depth |
454.0mm (17.9") |
532.0mm (20.9") |
| Weight |
37.40kg (82.3lbs) |
16.00kg (35.2lbs) |
| Enclosure |
Acoustic Suspension |
Bass Reflex |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
|
2 Years |
| Labor Warranty |
|
2 Years |