In this review, we will be comparing R-121SW and SPL-150, two Powered Subwoofer speakers by 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 Klipsch R-121SW and Klipsch SPL-150 first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the Klipsch R-121SW and Klipsch SPL-150 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 Klipsch R-121SWand Klipsch SPL-150 have a single woofer setup however the Klipsch R-121SW's woofer is 12-inch whereas the Klipsch SPL-150 features a 15-inch woofer.
Frequency Response
R-121SW has a frequency range of 28-120 Hz whereas SPL-150 has a frequency range of 18-125 Hz. With a minimum frequency of 18Hz, the SPL-150 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
Both Klipsch R-121SW and Klipsch SPL-150 have Bass Reflex type cabinets. 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 Klipsch R-121SW's and Klipsch SPL-150's external dimensions. Klipsch R-121SW has external dimensions of 423.0 x 407.0 x 532.0mm ( 16-5/8inch x 16inch x 20-15/16inch ) whereas Klipsch SPL-150 has external dimensions of 547.0 x 496.0 x 604.0mm ( 21-1/2 x 19-1/2 x 23-3/4inch) .
Klipsch SPL-150 is clearly the larger of the two speakers. Its body is 89mm wider, 124mm taller and 72mm deeper than Klipsch R-121SW.
Below you can see the front view size comparison of Klipsch R-121SW and Klipsch SPL-150 in scale.
Comparison image of Klipsch R-121SW and Klipsch SPL-150 Size and External Dimensions
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 R-121SW is approximately 2165.2cm2 / 335.6inch2 and base area of the Klipsch SPL-150 is approximately 2995.8cm2 / 464.3inch2. The R-121SW requires 28% less surface area than the SPL-150 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 Klipsch R-121SW weighs 16.00kg / 35.2lbs and the Klipsch SPL-150 weighs 34.27kg / 75.4lbs. This makes the SPL-150 114% heavier than the R-121SW.
Here is a comparison of how R-121SW and SPL-150's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of Klipsch R-121SW?
Here are the items that are included inside the box of R-121SW:
Powered subwooferGrille6.5-feet AC power cordUser ManualImportant Safety InstructionsWarranty Information
What's in the Box of Klipsch SPL-150?
Here are the items that come with the SPL-150:
Powered subGrille6.5-feet AC power cordUser ManualImportant Safety InstructionsWarranty Information
 Height |
423mm
vs
547mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
2165cm2 (407x532mm)
vs
2995cm2 (496x604mm)
|
Takes less floor space |
 Price per pair* |
599USD
vs
1399USD
|
costs less (*prices may change depending on the seller, location and time) |
 Woofer Size |
15 inches
vs
12 inches
|
Larger woofer |
| Low Frequency Response |
18 Hz
vs
28 Hz
|
Generates deeper bass |
 High Frequency Response |
125k Hz
vs
120k Hz
|
Generates higher frequency |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
| General |
Klipsch Reference R-121SW |
Klipsch SPL-150 |
| Brand |
Klipsch |
Klipsch |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
200 watts |
400 watts |
| Frequency Response |
28-120 Hz |
18-125 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
200-watt RMS |
400-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
15" |
| Woofer Composition |
Spun-Copper TCP |
Cerametallic |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
423.0mm (16.7") |
547.0mm (21.5") |
| Width |
407.0mm (16") |
496.0mm (19.5") |
| Depth |
532.0mm (20.9") |
604.0mm (23.8") |
| Weight |
16.00kg (35.2lbs) |
34.27kg (75.4lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
2 Years |
| Labor Warranty |
2 Years |
2 Years |