In this review, we will be comparing XT20 and A120, two Passive Bookshelf speakers from Polk Audio and JBL.
Let's have a brief look at the main features
of Polk XT20 and JBL A120 first before getting into our more
detailed comparison.
Polk XT20 Key Specs
- 2-way Design
- 1" Soft-Dome Tweeter
- 6.5" Bi-laminate paper Woofer
- 38-40k Hz Frequency Response
- 87 dB Sensitivity
- Impedance: 8ohms
- Power Range:30-200watts
- Weight:5.45kg
- Dimensions (H x W x D): 332.0" x 7-9/16" x 11-1/16"( 332.0 x 193.0 x 281.0mm )
JBL A120 Key Specs
- 2-way Design
- 1" Hard-Dome Tweeter
- 4.5" Polycellulose Woofer
- 60-40k Hz Frequency Response
- 86 dB Sensitivity
- Impedance: 6ohms
- Power Range:20-125watts
- Weight:3.82kg
- Dimensions (H x W x D): 286.0" x 6-3/4" x 7-7/16"( 286.0 x 172.0 x 189.0mm )
What size room are the Polk XT20 and JBL A120 speakers good for?
The size of the room in which you are planning to use these loudspeakers is an important decision
factor. Here we have compared their suitability to various sizes of environments considering their size
and max power parameters:
| Listening Environment* |
Polk XT20 |
JBL A120 |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Average |
| Very Large Room |
Poor |
Poor |
(* Approximate Room sizes: Small < 100sq. ft / 9 m2,
Mid-size: 100-220 sq. ft / 9-20 m2, Large 220-400 sq. ft / 20-36 m2, Very Large: >
400 sq. ft / 36 m2.
Average Floor Height: 9" / 2.7m. Typical room sizes differ from country to country, and the actual
listening experience changes depending on floor height, room shape, surface materials, listening
position, speaker locations, etc.)
In the following sections, we will get into more detail in order to better understand how the Polk XT20 and JBL A120 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both XT20 and A120 are 2-way speakers.
| Driver |
Polk XT20 |
JBL A120 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 6.5-inch
|
1 x 4.5-inch
|
XT20 features a 1" Soft-Dome Tweeter and 1 x 6.5" Bi-laminate paper Woofer . On the other hand, the A120 features a 1" aluminum Hard-Dome Tweeter and 1 x 4.5" Polycellulose Woofer .
Frequency Response
XT20 has a frequency range of 38-40k Hz whereas A120 has a frequency range of 60-40k Hz. With a minimum frequency of 38Hz, the XT20 can go significantly deeper on the low side and provide stronger bass compared to the A120's min frequency of 60Hz.
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 Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf Speakers
None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
XT20 is a 8 ohms speaker compared to the A120 which has a nominal impedance of 6 ohms.
These two speakers also have different sensitivity levels. XT20 sensitivity is rated at 87 dB and the A120's is rated at 86 dB. This 1 dB difference makes the Polk XT20 a more sensitive speaker compared to JBL A120, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf Speakers
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using
an amplifier within this range ensures the nominal performance , inputting a power that is higher than the
max wattage can result in a damaged speaker.
XT20 can handle a max power of 200 watts RMS from the amp the whereas A120 has a max power handling value of 125 watts RMS, 75 watts less than the XT20.
Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker
compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters
such as Impedance, sensitivity and system efficiencies.
Input Type and Bi-Amping / Bi-Wiring
XT20 features 5-way post type posts and A120 has a 5-way post type posts. None of these speakers feature bi-amping/bi-wiring.
JBL A120's 5-way post terminals
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 Polk XT20's and JBL A120's external dimensions. Polk XT20 has external dimensions of 332.0 x 193.0 x 281.0mm ( 13-1/16 x 7-9/16 x 11-1/16inch) whereas JBL A120 has external dimensions of 286.0 x 172.0 x 189.0mm ( 11-1/4 x 6-3/4 x 7-7/16inch) .
Polk XT20 is clearly the larger of the two speakers. Its body is 21mm wider, 46mm taller and 92mm deeper than JBL A120.
Below you can see the front view size comparison of Polk XT20 and JBL A120 in scale.
Comparison image of Polk XT20 and JBL A120 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 Polk XT20 is approximately 542.3cm2 / 84.1inch2 and base area of the JBL A120 is approximately 325.1cm2 / 50.4inch2. The XT20 requires 67% more surface area than the A120 which gives it a small disadvantage on placement in tight spaces.
Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:
Size Comparison image of Polk XT20 and JBL A120 on a Media Console