In this review, we will be comparing Radius 390 and A120P, two Powered Subwoofer speakers from Monitor Audio 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 Monitor Audio Radius 390 and JBL Stage A120P first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the Monitor Audio Radius 390 and JBL Stage A120P 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 Monitor Audio Radius 390and JBL Stage A120P have a single woofer setup however the Monitor Audio Radius 390's woofer is 10-inch whereas the JBL Stage A120P features a 12-inch woofer.
Frequency Response
Radius 390 has a frequency range of 30-120 Hz whereas A120P has a frequency range of 32-150 Hz. With a minimum frequency of 30Hz, the Radius 390 can go slightly deeper then 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
High Frequency
Subwoofer Speakers
Cabinet Type
The Monitor Audio Radius 390 has a Passive Radiator type cabinet. Passive Radiator type subwoofers sports a non-powered cone that moves in response to the main woofer to move air out in order to generate stronger bass in a smaller body compared to ported or sealed designs. On the other hand the JBL Stage A120P have Bass reflex type enclosure.
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 Monitor Audio Radius 390's and JBL Stage A120P's external dimensions. Monitor Audio Radius 390 has external dimensions of 348.0 x 331.0 x 385.0mm ( 13-11/16 x 13 x 15-1/8inch) 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) .
JBL Stage A120P is clearly the larger of the two speakers. Its body is 62mm wider, 67mm taller and 90mm deeper than Monitor Audio Radius 390.
Below you can see the front view size comparison of Monitor Audio Radius 390 and JBL Stage A120P in scale.
Comparison image of Monitor Audio Radius 390 and JBL Stage A120P 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 Monitor Audio Radius 390 is approximately 1274.4cm2 / 197.5inch2 and base area of the JBL Stage A120P is approximately 1866.8cm2 / 289.4inch2. The Radius 390 requires 32% less surface area than the A120P 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 Monitor Audio Radius 390 weighs 13.77kg / 30.3lbs and the JBL Stage A120P weighs 18.68kg / 41.1lbs. This makes the A120P 36% heavier than the Radius 390.
Here is a comparison of how Radius 390 and A120P's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of Monitor Audio Radius 390?
Here are the items that are included inside the box of Radius 390:
Powered sub6-feet AC power cord10.75-feet Mono minijack cableOwners ManualImportant Safety Instructions
What's in the Box of JBL Stage A120P?
Here are the items that come with the A120P:
Powered subwooferGrille6-feet AC power cord4 Spike feetOwners ManualWarranty CardImportant Safety Instructions
 Low Frequency Response |
30 Hz
vs
32 Hz
|
Generates deeper bass |
 Height |
348mm
vs
415mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1274cm2 (331x385mm)
vs
1866cm2 (393x475mm)
|
Takes less floor space |
| Woofer Size |
12 inches
vs
10 inches
|
Larger woofer |
 High Frequency Response |
150k Hz
vs
120k Hz
|
Generates higher frequency |
 Price per pair* |
300USD
vs
1150USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Monitor Audio Radius 390 |
JBL Stage A120P |
| Brand |
Monitor Audio |
JBL |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
220 watts |
250 watts |
| Frequency Response |
30-120 Hz |
32-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
220-watt RMS |
250-watt RMS |
| Watts Peak (Max) |
n/a |
500-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
10" |
12" |
| Woofer Composition |
C-CAM |
Polycellulose |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
side |
front |
Physical Specs |
|
|
| Height |
348.0mm (13.7") |
415.0mm (16.3") |
| Width |
331.0mm (13") |
393.0mm (15.5") |
| Depth |
385.0mm (15.2") |
475.0mm (18.7") |
| Weight |
13.77kg (30.3lbs) |
18.68kg (41.1lbs) |
| Enclosure |
Passive Radiator |
Bass reflex |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
1 Year |
| Labor Warranty |
2 Years |
1 Year |