In this review, we will be comparing A120P and SX-120, two Powered Subwoofer speakers from JBL and Cambridge Audio. 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 JBL Stage A120P and Cambridge Audio SX-120 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 JBL Stage A120Pand Cambridge Audio SX-120 have a single woofer setup however the JBL Stage A120P's woofer is 12-inch whereas the Cambridge Audio SX-120 features a 8-inch woofer.
Frequency Response
A120P has a frequency range of 32-150 Hz whereas SX-120 has a frequency range of 34-150 Hz. With a minimum frequency of 32Hz, the A120P can go slightly deeper then the SX-120's min frequency of 34Hz.
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 JBL Stage A120P has a Bass reflex type cabinet. On the other hand the Cambridge Audio SX-120 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.
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 JBL Stage A120P's and Cambridge Audio SX-120's external dimensions. 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) whereas Cambridge Audio SX-120 has external dimensions of 296.0 x 297.0 x 350.0mm (11-5/8 x 11-11/16 x 13-3/4inch).
JBL Stage A120P is clearly the larger of the two speakers. Its body is 96mm wider, 119mm taller and 125mm deeper than Cambridge Audio SX-120.
Below you can see the front view size comparison of JBL Stage A120P and Cambridge Audio SX-120 in scale.
Comparison image of JBL Stage A120P and Cambridge Audio SX-120 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 JBL Stage A120P is approximately 1866.8cm2 / 289.4inch2 and base area of the Cambridge Audio SX-120 is approximately 1039.5cm2 / 161.1inch2. The A120P requires 80% more surface area than the SX-120 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 JBL Stage A120P weighs 18.68kg / 41.1lbs and the Cambridge Audio SX-120 weighs 7.73kg / 17lbs. This makes the A120P 142% heavier than the SX-120.
Here is a comparison of how A120P and SX-120's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of JBL Stage A120P?
Here are the items that are included inside the box of A120P:
- Powered subwoofer
- Grille
- 6-feet AC power cord
- 4 Spike feet
- Owners Manual
- Warranty Card
- Important Safety Instructions
What's in the Box of Cambridge Audio SX-120?
Here are the items that come with the SX-120:
- Powered subwoofer
- 6-feet AC power cord
- Grille
- 4 Spiked feet
- Installation Guide
- Important Safety Instructions
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
| Low Frequency Response |
32 Hz
vs
34 Hz
|
Generates deeper bass |
 Price per pair* |
300USD
vs
319USD
|
costs less (*prices may change depending on the seller, location and time) |
 Height |
296mm
vs
415mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1039cm2
vs
1866cm2
|
Takes less floor space |
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.
JBL Stage A120P needs about 80% more floor area. JBL Stage A120P stands 125mm further into the room. JBL Stage A120P is 119mm taller.
| General |
JBL Stage A120P |
Cambridge Audio SX-120 |
| Brand |
JBL |
Cambridge Audio |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
250 watts |
70 watts |
| Frequency Response |
32-150 Hz |
34-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
250-watt RMS |
70-watt RMS |
| Watts Peak (Max) |
500-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
8" |
| Woofer Composition |
Polycellulose |
Treated Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
415.0mm (16.3") |
296.0mm (11.7") |
| Width |
393.0mm (15.5") |
297.0mm (11.7") |
| Depth |
475.0mm (18.7") |
350.0mm (13.8") |
| Weight |
18.68kg (41.1lbs) |
7.73kg (17lbs) |
| Enclosure |
Bass reflex |
Bass Reflex |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
1 Year |
3 Years |
| Labor Warranty |
1 Year |
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 (32Hz vs 34Hz). |
| Amplifier power | A | JBL Stage A120P has the bigger amplifier - 250W against 70W RMS, about 5.5dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | A | JBL Stage A120P 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. |
| Cabinet size | depends | Cambridge Audio SX-120 is about 60% 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 | Cambridge Audio SX-120 carries 3 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 | A | JBL Stage A120P costs less - $300 against $319, about 6% less. |
A JBL Stage A120P B Cambridge Audio SX-120
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?
JBL Stage A120P has the edge on paper, though not by much. The "depends" rows are more likely to decide this than the score is. If placement is the constraint - a corner, behind a sofa, under a desk - Cambridge Audio SX-120 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.