In this review, we will be comparing R-121SW and S8, two Powered Subwoofer speakers from Klipsch and Audioengine. 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 Audioengine S8 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 R-121SWand Audioengine S8 have a single woofer setup however the Klipsch R-121SW's woofer is 12-inch whereas the Audioengine S8 features a 8-inch woofer.
Frequency Response
R-121SW has a frequency range of 28-120 Hz whereas S8 has a frequency range of 27-180 Hz. With a minimum frequency of 27Hz, the S8 can go slightly deeper then 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 Audioengine S8 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
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 R-121SW's and Audioengine S8'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 Audioengine S8 has external dimensions of 334.0 x 293.0 x 337.0mm (13-1/8 x 11-1/2 x 13-1/4inch).
Klipsch R-121SW is clearly the larger of the two speakers. Its body is 114mm wider, 89mm taller and 195mm deeper than Audioengine S8.
Below you can see the front view size comparison of Klipsch R-121SW and Audioengine S8 in scale.
Comparison image of Klipsch R-121SW and Audioengine S8 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 Audioengine S8 is approximately 987.4cm2 / 153.0inch2. The R-121SW requires 119% more surface area than the S8 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 R-121SW weighs 16.00kg / 35.2lbs and the Audioengine S8 weighs 13.64kg / 30lbs. This makes the R-121SW 17% heavier than the S8.
Here is a comparison of how R-121SW and S8'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 subwoofer
- Grille
- 6.5-feet AC power cord
- User Manual
- Important Safety Instructions
- Warranty Information
What's in the Box of Audioengine S8?
Here are the items that come with the S8:
- Powered subwoofer
- 6-feet AC power cord
- 6.5-feet Stereo RCA cable
- 6.5-feet Stereo minijack audio cable
- Cloth subwoofer bag
- Cloth cable bag
- Quick Start Guide
- Audioengine brochure
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
27 Hz
vs
28 Hz
|
Generates deeper bass |
 High Frequency Response |
180 Hz
vs
120 Hz
|
Generates higher frequency |
 Height |
334mm
vs
423mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
987cm2
vs
2165cm2
|
Takes less floor space |
 Price per pair* |
349USD
vs
599USD
|
costs less (*prices may change depending on the seller, location and time) |
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 R-121SW needs about 119% more floor area. Klipsch R-121SW stands 195mm further into the room. Klipsch R-121SW is 89mm taller.
| General |
Klipsch Reference R-121SW |
Audioengine S8 |
| Brand |
Klipsch |
Audioengine |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
200 watts |
125 watts |
| Frequency Response |
28-120 Hz |
27-180 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
200-watt RMS |
125-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
8" |
| Woofer Composition |
Spun-Copper TCP |
Treated paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
bottom |
Physical Specs |
|
|
| Height |
423.0mm (16.7") |
334.0mm (13.1") |
| Width |
407.0mm (16") |
293.0mm (11.5") |
| Depth |
532.0mm (20.9") |
337.0mm (13.3") |
| Weight |
16.00kg (35.2lbs) |
13.64kg (30lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
3 Years |
| Labor Warranty |
2 Years |
3 Years |
Two quite different sizes of subwoofer. Room volume decides this more than anything else on the page: a big driver in a small room is wasted, and a small one in a large room is worked to death.
| Area | Better | Why |
|---|
| Bass depth | evenly matched | Effectively the same reach (28Hz vs 27Hz). |
| Amplifier power | A | Klipsch R-121SW has the bigger amplifier - 200W against 125W RMS, about 2dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | Klipsch R-121SW moves more air: 12" against 8" is 2.25x the cone area, not the 1.5x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | evenly matched | Both are ported designs, so they roll off in much the same way. |
| Driver placement | depends | Klipsch R-121SW fires front and Audioengine S8 fires 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 | Audioengine S8 is about 64% 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. |
| Warranty | B | Audioengine S8 carries 3 years on parts against 2 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | B | Audioengine S8 costs less - $349 against $599, about 42% less. |
A Klipsch R-121SW B Audioengine S8
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 R-121SW is ahead, but on only 1 of the measured areas, and it costs about 72% more. Audioengine S8 is the sensible buy unless your room is large enough to need the extra. Two small subwoofers beat one big one in most rooms - a pair evens out the room modes in a way no single box can, whatever its specs. At $349 each, two Audioengine S8 cost about $698 against $599 for one of the other, which is worth a thought. If placement is the constraint - a corner, behind a sofa, under a desk - Audioengine S8 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.