In this review, we will be comparing Monitor XT30 and A135C, two Passive Center Channel speakers from Polk Audio and JBL. Let's have a brief look at the main features
of Polk XT30 and JBL Stage A135C first before getting into our more
detailed comparison.
What size room are the Polk XT30 and JBL Stage A135C 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:
In the following sections, we will get into more detail in order to better understand how the Polk XT30 and JBL Stage A135C 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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Drivers
Both Monitor XT30 and A135C are 2-way speakers.
Driver |
Polk XT30 |
JBL Stage A135C |
Driver Setup
|
2-way
|
2-way
|
Tweeter
|
1-inch
|
1-inch
|
Midrange
|
- |
- |
Woofer
|
2 x 5.25-inch
|
6 x 3-inch
|
Monitor XT30 features a 1" Terylene High-res dome Tweeter and 2 x 5.25" bi-laminate paper cone Woofer . On the other hand, the A135C features a 1" aluminum dome with HDI (High Definition Imaging) waveguide technology Tweeter and 6 x 3" polycellulose Woofer .
Frequency Response
Monitor XT30 has a frequency range of 55-40k Hz whereas A135C has a frequency range of 75-40k 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 A135C'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
Monitor XT30 is a 8 ohms speaker compared to the A135C which has a nominal impedance of 6 ohms.
These two speakers also have different sensitivity levels. Monitor XT30 sensitivity is rated at 89 dB and the A135C's is rated at 90 dB. This 1 dB difference makes the JBL Stage A135C a more sensitive speaker compared to Polk XT30, 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.
Monitor XT30 can handle a max power of 200 watts RMS from the amp the whereas A135C 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
Monitor XT30 features 5-way post type posts and A135C has a 5-way post type posts. None of these speakers feature bi-amping/bi-wiring.
Cabinet Type and Port Position
Monitor XT30 has a rear firing port whereas A135C has a side firing ports.
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 XT30's and JBL Stage A135C's external dimensions. 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) whereas JBL Stage A135C has external dimensions of 105.0 x 747.0 x 186.0mm ( 4-1/8 x 29-3/8 x 7-5/16inch) .
JBL Stage A135C is 61mm shorter and 22mm less deeper than Polk XT30 but it is also 262mm 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 Polk XT30 is approximately 1008.8cm2 / 156.4inch2 and base area of the JBL Stage A135C is approximately 1389.4cm2 / 215.4inch2. The Monitor XT30 requires 27% less surface area than the A135C which gives it a small advantage 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 Polk XT30 weighs 5.91kg / 13lbs and the JBL Stage A135C weighs 7.46kg / 16.4lbs. This makes the A135C 26% heavier than the Monitor XT30.
Here is a comparison of how Monitor XT30 and A135C'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 Polk XT30?
Here are the items that are included inside the box of Monitor XT30:
Center-channel loudspeakerGrille (attached)4 Self-adhesive rubber feetOwners ManualOnline Product RegistrationWall-Mount Template
What's in the Box of JBL Stage A135C?
Here are the items that come with the A135C:
Center-channel loudspeakerGrille4 Leveling feet4 Rubber feetOwners ManualWarranty Card
Max Input Power |
200 watts
vs
150 watts
|
Handle more power from your amplifier |
Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
Woofer Size |
5.25 inches
vs
3 inches
|
Larger woofer |
Low Frequency Response |
55 Hz
vs
75 Hz
|
Generates deeper bass |
Base Surface Area |
1008cm2 (485x208mm)
vs
1389cm2 (747x186mm)
|
Takes less floor space |
Price per pair* |
199USD
vs
300USD
|
costs less (*prices may change depending on the seller, location and time) |
Sensitivity |
90 dB
vs
89 dB
|
Play louder with same amount of amplification power |
Number of Woofers |
6
vs
2
|
More woofers |
Height |
105mm
vs
166mm
|
Easier to fit in smaller spaces |
General |
Polk Audio Monitor XT30 |
JBL Stage A135C |
Brand |
Polk Audio |
JBL |
Speaker Type |
Center channel speaker |
Low-profile center channel speaker |
Power Range |
30-200 watts |
20-150 watts |
Sensitivity |
89 dB |
90 dB |
Impedance |
8 ohms |
6 ohms |
Frequency Response |
55-40k Hz |
75-40k Hz |
Drivers |
|
|
Woofer Quantity |
2 |
6 |
Woofer Size |
5.25" |
3" |
Woofer Composition |
bi-laminate paper cone |
polycellulose |
Tweeter Size |
1" |
1" |
Tweeter Type |
High-res dome |
dome with HDI (High Definition Imaging) waveguide technology |
Aimable Tweeter |
No |
No |
Midrange Driver |
N/A" |
N/A" |
Firing Direction |
rear |
side |
Physical Specs |
|
|
Height |
166.0mm (6.5") |
105.0mm (4.1") |
Width |
485.0mm (19.1") |
747.0mm (29.4") |
Depth |
208.0mm (8.2") |
186.0mm (7.3") |
Weight |
5.91kg (13lbs) |
7.46kg (16.4lbs) |
Enclosure |
Bass Reflex |
Bass Reflex |
Available Colors |
Black |
Black |
Grille |
Yes |
Yes |
Moisture Resistancy |
No |
No |
Connections |
|
|
Biamp Inputs |
n/a |
No |
Other |
|
|
Parts Warranty |
5 Years |
5 Years |
Labor Warranty |
5 Years |
5 Years |