In this review, we will be comparing PB17 Ultra R Evolution and A120P, two Powered Subwoofer speakers from SVS and JBL. 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 SVS PB17 Ultra R Evolution and JBL Stage A120P 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 SVS PB17 Ultra R Evolutionand JBL Stage A120P have a single woofer setup however the SVS PB17 Ultra R Evolution's woofer is 17-inch whereas the JBL Stage A120P features a 12-inch woofer.
Frequency Response
PB17 Ultra R Evolution has a frequency range of 14-220 Hz whereas A120P has a frequency range of 32-150 Hz. With a minimum frequency of 14Hz, the PB17 Ultra R Evolution can go significantly deeper on the low side and provide stronger bass compared to the A120P's min frequency of 32Hz.
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
SVS PB17 Ultra R Evolution
High Frequency
Subwoofer Speakers
SVS PB17 Ultra R Evolution
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 SVS PB17 Ultra R Evolution's and JBL Stage A120P's external dimensions. SVS PB17 Ultra R Evolution has external dimensions of 635.0 x 552.5 x 746.1mm () whereas JBL Stage A120P has external dimensions of 415.0 x 393.0 x 475.0mm (16-5/16 x 15-7/16 x 18-11/16inch).
SVS PB17 Ultra R Evolution is clearly the larger of the two speakers. Its body is 159.5mm wider, 220mm taller and 271.1mm deeper than JBL Stage A120P.
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 SVS PB17 Ultra R Evolution is approximately 4122.2cm2 / 638.9inch2 and base area of the JBL Stage A120P is approximately 1866.8cm2 / 289.4inch2. The PB17 Ultra R Evolution requires 121% more surface area than the A120P 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 SVS PB17 Ultra R Evolution weighs 74.71kg / 164.4lbs and the JBL Stage A120P weighs 18.68kg / 41.1lbs. This makes the PB17 Ultra R Evolution 300% heavier than the A120P.
Here is a comparison of how PB17 Ultra R Evolution and A120P's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
SVS PB17 Ultra R Evolution
 Woofer Size |
17 inches
vs
12 inches
|
Larger woofer |
| Low Frequency Response |
14 Hz
vs
32 Hz
|
Generates deeper bass |
 High Frequency Response |
220 Hz
vs
150 Hz
|
Generates higher frequency |
 Height |
415mm
vs
635mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1866cm2
vs
4122cm2
|
Takes less floor space |
 Price per pair* |
300USD
vs
3000USD
|
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.
SVS PB17 Ultra R Evolution needs about 121% more floor area. SVS PB17 Ultra R Evolution stands 271mm further into the room. SVS PB17 Ultra R Evolution is 220mm taller.
| General |
SVS PB17 Ultra R Evolution |
JBL Stage A120P |
| Brand |
SVS |
JBL |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
14-220 Hz |
32-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
2800-watt RMS |
250-watt RMS |
| Watts Peak (Max) |
6000-watt RMS |
500-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
17" |
12" |
| Woofer Composition |
|
Polycellulose |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
front |
Physical Specs |
|
|
| Height |
635.0mm (25") |
415.0mm (16.3") |
| Width |
552.5mm (21.8") |
393.0mm (15.5") |
| Depth |
746.1mm (29.4") |
475.0mm (18.7") |
| Weight |
74.71kg (164.4lbs) |
18.68kg (41.1lbs) |
| Enclosure |
|
Bass reflex |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
5 Years |
1 Year |
| Labor Warranty |
5 Years |
1 Year |
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 | A | SVS PB17 Ultra R Evolution goes deeper - 14Hz against 32Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | A | SVS PB17 Ultra R Evolution has the bigger amplifier - 2800W against 250W RMS, about 10.5dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | SVS PB17 Ultra R Evolution moves more air: 17" against 12" is 2.01x the cone area, not the 1.42x 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. |
| Cabinet size | depends | JBL Stage A120P is about 70% 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 | A | SVS PB17 Ultra R Evolution carries 5 years on parts against 1 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | B | JBL Stage A120P costs less - $300 against $3,000, about 90% less. |
A SVS PB17 Ultra R Evolution B JBL Stage A120P
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 PB17 Ultra R Evolution measures better, JBL Stage A120P costs about 90% 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 $300 each, two JBL Stage A120P cost about $600 against $3,000 for one of the other, which is worth a thought. If placement is the constraint - a corner, behind a sofa, under a desk - JBL Stage A120P 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.