In this review, we will be comparing A125C and Monitor XT30, two Passive Center Channel speakers from JBL and Polk Audio.
Let's have a brief look at the main features
of JBL Stage A125C and Polk XT30 first before getting into our more
detailed comparison.
JBL Stage A125C Key Specs
- 2-way Design
- 1" dome with HDI (High Definition Imaging) waveguide technology Tweeter
- 2 x 5.24" polycellulose Woofer
- 75-40k Hz Frequency Response
- 88 dB Sensitivity
- Impedance: 6ohms
- Power Range:20-150watts
- Weight:7.97kg
- Dimensions (H x W x D): 191.0" x 18-1/2" x 9-1/2"( 191.0 x 470.0 x 242.0mm )
Polk XT30 Key Specs
- 2-way Design
- 1" High-res dome Tweeter
- 2 x 5.25" bi-laminate paper cone Woofer
- 55-40k Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:30-200watts
- Weight:5.91kg
- Dimensions (H x W x D): 166.0" x 19-1/16" x 8-3/16"( 166.0 x 485.0 x 208.0mm )
What size room are the JBL Stage A125C and Polk XT30 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* |
JBL Stage A125C |
Polk XT30 |
| 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 JBL Stage A125C and Polk XT30 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
**This post contains affiliate links, and I will be compensated if you make a purchase after clicking
through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both A125C and Monitor XT30 are 2-way speakers.
| Driver |
JBL Stage A125C |
Polk XT30 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5.24-inch
|
2 x 5.25-inch
|
A125C features a 1" aluminum dome with HDI (High Definition Imaging) waveguide technology Tweeter and 2 x 5.24" polycellulose Woofer . On the other hand, the Monitor XT30 features a 1" Terylene High-res dome Tweeter and 2 x 5.25" bi-laminate paper cone Woofer .
Frequency Response
A125C has a frequency range of 75-40k Hz whereas Monitor XT30 has a frequency range of 55-40k Hz. With a minimum frequency of 55Hz, the Monitor XT30 can go significantly deeper on the low side and provide stronger bass compared to the A125C's min frequency of 75Hz.
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 Center Channel class in our database.
Low Frequency
Center Channel Speakers
High Frequency
Center Channel 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
A125C is a 6 ohms speaker compared to the Monitor XT30 which has a nominal impedance of 8 ohms.
These two speakers also have different sensitivity levels. A125C sensitivity is rated at 88 dB and the Monitor XT30's is rated at 89 dB. This 1 dB difference makes the Polk XT30 a more sensitive speaker compared to JBL Stage A125C, hence will play louder with the same amount of watts.
Sensitivity
Center Channel 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.
A125C can handle a max power of 200 watts RMS from the amp the whereas A125C has a max power handling value of 150 watts RMS , 50 watts less than the Monitor XT30.
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
A125C features 5-Way post type posts and Monitor XT30 has a 5-Way post type posts. None of these speakers feature bi-amping/bi-wiring.
JBL Stage A125C's 5-Way post terminals
Polk XT30'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 JBL Stage A125C's and Polk XT30's external dimensions. JBL Stage A125C has external dimensions of 191.0 x 470.0 x 242.0mm ( 7-1/2 x 18-1/2 x 9-1/2inch) whereas Polk XT30 has external dimensions of 166.0 x 485.0 x 208.0mm ( 6-1/2 x 19-1/16 x 8-3/16inch) .
Polk XT30 is 25mm shorter and 34mm less deeper than JBL Stage A125C but it is also 15mm wider.
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 A125C is approximately 1137.4cm2 / 176.3inch2 and base area of the Polk XT30 is approximately 1008.8cm2 / 156.4inch2. The A125C requires 13% more surface area than the Monitor XT30 which gives it a small disadvantage on placement in tight spaces.
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The JBL Stage A125C weighs 7.97kg / 17.5lbs and the Polk XT30 weighs 5.91kg / 13lbs. This makes the A125C 35% heavier than the Monitor XT30.
Here is a comparison of how A125C and Monitor XT30's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
What's in the Box of JBL Stage A125C?
Here are the items that are included inside the box of A125C:
Center-channel loudspeakerGrille4 Leveling feet4 Rubber feetOwners ManualWarranty Card
What's in the Box of Polk XT30?
Here are the items that come with the Monitor XT30:
Center-channel loudspeakerGrille (attached)4 Self-adhesive rubber feetOwners ManualOnline Product RegistrationWall-Mount Template
 Max Input Power |
200 watts
vs
150 watts
|
Handle more power from your amplifier |
 Sensitivity |
89 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Woofer Size |
5.25 inches
vs
5.24 inches
|
Larger woofer |
|
Low Frequency Response |
55 Hz
vs
75 Hz
|
Generates deeper bass |
 Height |
166mm
vs
191mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1008cm2
vs
1137cm2
|
Takes less floor space |
 Price per pair* |
199USD
vs
350USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
JBL Stage A125C |
Polk Audio Monitor XT30 |
| Brand |
JBL |
Polk Audio |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
20-150 watts |
30-200 watts |
| Sensitivity |
88 dB |
89 dB |
| Impedance |
6 ohms |
8 ohms |
| Frequency Response |
75-40k Hz |
55-40k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5.24" |
5.25" |
| Woofer Composition |
polycellulose |
bi-laminate paper cone |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
dome with HDI (High Definition Imaging) waveguide technology |
High-res dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
N/A" |
N/A" |
| Firing Direction |
n/a |
rear |
Physical Specs |
|
|
| Height |
191.0mm (7.5") |
166.0mm (6.5") |
| Width |
470.0mm (18.5") |
485.0mm (19.1") |
| Depth |
242.0mm (9.5") |
208.0mm (8.2") |
| Weight |
7.97kg (17.5lbs) |
5.91kg (13lbs) |
| Enclosure |
Passive Radiator |
Bass Reflex |
| Available Colors |
Black |
Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
n/a |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |