In this review, we will be comparing R-121SW and PC-4000, two Powered Subwoofer speakers from Klipsch and SVS. 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 SVS PC-4000 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.
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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 SVS PC-4000 have a single woofer setup however the Klipsch R-121SW's woofer is 12-inch whereas the SVS PC-4000 features a 13.5-inch woofer.
Frequency Response
R-121SW has a frequency range of 28-120 Hz whereas PC-4000 has a frequency range of 17-200 Hz. With a minimum frequency of 17Hz, the PC-4000 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 SVS PC-4000 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 SVS PC-4000'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 SVS PC-4000 has external dimensions of 1194.0 x 423.0 x 423.0mm (47 x 16-5/8 x 16-5/8inch).
Klipsch R-121SW is 16mm narrower and 771mm shorter than SVS PC-4000 but it is also 109mm deeper.
Below you can see the front view size comparison of Klipsch R-121SW and SVS PC-4000 in scale.
Comparison image of Klipsch R-121SW and SVS PC-4000 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 SVS PC-4000 is approximately 1789.3cm2 / 277.3inch2. The R-121SW requires 21% more surface area than the PC-4000 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 SVS PC-4000 weighs 42.00kg / 92.4lbs. This makes the PC-4000 163% heavier than the R-121SW.
Here is a comparison of how R-121SW and PC-4000'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 SVS PC-4000?
Here are the items that come with the PC-4000:
- Powered subwoofer
- Top-cap w/ integrated grille
- 6-feet AC power cord
- Remote control
- 4 Elastomer feet
- Owners Manual
- Important Safety Instructions
 Height |
423mm
vs
1194mm
|
Easier to fit in smaller spaces |
 Price per pair* |
599USD
vs
2200USD
|
costs less (*prices may change depending on the seller, location and time) |
 Woofer Size |
13.5 inches
vs
12 inches
|
Larger woofer |
| Low Frequency Response |
17 Hz
vs
28 Hz
|
Generates deeper bass |
 High Frequency Response |
200 Hz
vs
120 Hz
|
Generates higher frequency |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
 Base Surface Area |
1789cm2
vs
2165cm2
|
Takes less floor space |
| General |
Klipsch Reference R-121SW |
SVS PC-4000 |
| Brand |
Klipsch |
SVS |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
200 watts |
1200 watts |
| Frequency Response |
28-120 Hz |
17-200 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
200-watt RMS |
1200-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
13.5" |
| Woofer Composition |
Spun-Copper TCP |
Composite/Glass Fiber |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
bottom |
Physical Specs |
|
|
| Height |
423.0mm (16.7") |
1194.0mm (47") |
| Width |
407.0mm (16") |
423.0mm (16.7") |
| Depth |
532.0mm (20.9") |
423.0mm (16.7") |
| Weight |
16.00kg (35.2lbs) |
42.00kg (92.4lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
5 Years |
| Labor Warranty |
2 Years |
5 Years |
Different price classes - SVS PC-4000 costs roughly 3.7x what Klipsch R-121SW does. Before paying it, read the note below about two smaller subwoofers.
| Area | Better | Why |
|---|
| Bass depth | B | SVS PC-4000 goes deeper - 17Hz against 28Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | B | SVS PC-4000 has the bigger amplifier - 1200W against 200W RMS, about 7.8dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | SVS PC-4000 moves more air: 13.5" against 12" is 1.27x the cone area, not the 1.13x 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 SVS PC-4000 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 | Klipsch R-121SW is about 57% 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 | SVS PC-4000 carries 5 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 | A | Klipsch R-121SW costs less - $599 against $2,200, about 73% less. |
A Klipsch R-121SW B SVS PC-4000
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?
The usual trade-off: SVS PC-4000 measures better, Klipsch R-121SW costs about 73% less. In a normal room, placement will make a bigger difference than the gap between these two. 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 $599 each, two Klipsch R-121SW cost about $1,198 against $2,200 for one of the other, which is worth a thought. If placement is the constraint - a corner, behind a sofa, under a desk - Klipsch R-121SW 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.