In this review, we will be comparing Motion 30i and Monitor XT35, two Passive Center Channel speakers from MartinLogan and Polk Audio. Let's have a brief look at the main features
of MartinLogan 30i and Polk XT35 first before getting into our more
detailed comparison.
What size room are the MartinLogan 30i and Polk XT35 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 MartinLogan 30i and Polk XT35 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 Motion 30i and Monitor XT35 are 2-way speakers.
Driver |
MartinLogan 30i |
Polk XT35 |
Driver Setup
|
2-way
|
2-way
|
Tweeter
|
1.0 x 1.4-inch
|
1-inch
|
Midrange
|
- |
- |
Woofer
|
1 x 5.25-inch
|
4 x 3-inch
|
Motion 30i features a 1.0 x 1.4" Folded Motion Tweeter and 1 x 5.25" Aluminum Woofer with a Crossover frequency at 400Hz and 2600Hz. On the other hand, the Monitor XT35 features a 1" Terylene High-res dome Tweeter and 4 x 3" bi-laminate paper cone Woofer .
Frequency Response
Motion 30i has a frequency range of 65-25k Hz whereas Monitor XT35 has a frequency range of 57-40k Hz. With a minimum frequency of 57Hz, the Monitor XT35 can go significantly deeper on the low side and provide stronger bass compared to the Motion 30i's min frequency of 65Hz.
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
Motion 30i is a 4 ohms speaker compared to the Monitor XT35 which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the Motion 30i can provide this impedance level.
These two speakers also have different sensitivity levels. Motion 30i sensitivity is rated at 91 dB and the Monitor XT35's is rated at 87 dB. This 4 dB difference makes the MartinLogan 30i a more sensitive speaker compared to Polk XT35, 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.
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
Motion 30i features 5-Way post type posts and Monitor XT35 has a 5-Way post type posts. None of these speakers feature bi-amping/bi-wiring.
Cabinet Type and Port Position
Both Motion 30i and Monitor XT35 have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
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 MartinLogan 30i's and Polk XT35's external dimensions. MartinLogan 30i has external dimensions of 177.0 x 423.0 x 281.0mm ( 6-15/16 x 16-5/8 x 11-1/16inch) whereas Polk XT35 has external dimensions of 107.0 x 621.0 x 142.0mm ( 4-3/16 x 24-7/16 x 5-9/16inch) .
Polk XT35 is 70mm shorter and 139mm less deeper than MartinLogan 30i but it is also 198mm 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 MartinLogan 30i is approximately 1188.6cm2 / 184.2inch2 and base area of the Polk XT35 is approximately 881.8cm2 / 136.7inch2. The Motion 30i requires 35% more surface area than the Monitor XT35 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 MartinLogan 30i weighs 8.18kg / 18lbs and the Polk XT35 weighs 6.36kg / 14lbs. This makes the Motion 30i 29% heavier than the Monitor XT35.
Here is a comparison of how Motion 30i and Monitor XT35'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 MartinLogan 30i?
Here are the items that are included inside the box of Motion 30i:
Center-channel loudspeaker Grille 4 Rubber feet Users Manual Warranty/Registration Information
What's in the Box of Polk XT35?
Here are the items that come with the Monitor XT35:
Center-channel loudspeakerGrille (attached)4 Self-adhesive rubber feetOwners ManualOnline Product RegistrationWall-Mount Template
Sensitivity |
91 dB
vs
87 dB
|
Play louder with same amount of amplification power |
Woofer Size |
5.25 inches
vs
3 inches
|
Larger woofer |
Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
Number of Woofers |
4
vs
1
|
More woofers |
Low Frequency Response |
57 Hz
vs
65 Hz
|
Generates deeper bass |
High Frequency Response |
40k Hz
vs
25k Hz
|
Generates higher frequency |
Height |
107mm
vs
177mm
|
Easier to fit in smaller spaces |
Base Surface Area |
881cm2 (621x142mm)
vs
1188cm2 (423x281mm)
|
Takes less floor space |
Price per pair* |
299USD
vs
900USD
|
costs less (*prices may change depending on the seller, location and time) |
General |
MartinLogan Motion 30i |
Polk Audio Monitor XT35 |
Brand |
MartinLogan |
Polk Audio |
Speaker Type |
Center channel speaker |
Low-profile center channel speaker |
Power Range |
20-200 watts |
25-200 watts |
Sensitivity |
91 dB |
87 dB |
Impedance |
4 ohms |
8 ohms |
Frequency Response |
65-25k Hz |
57-40k Hz |
Drivers |
|
|
Woofer Quantity |
1 |
4 |
Woofer Size |
5.25" |
3" |
Woofer Composition |
Aluminum |
bi-laminate paper cone |
Woofer Surround Material |
Rubber |
n/a |
Tweeter Size |
1.0 x 1.4" |
1" |
Tweeter Type |
Folded Motion |
High-res dome |
Aimable Tweeter |
No |
No |
Midrange Driver |
No |
N/A" |
Crossover Frequency |
400Hz and 2600Hz |
n/a |
Firing Direction |
rear |
rear |
Suggested Break-in Period |
Allow 72 hours of break-in at 90 dB |
n/a |
Physical Specs |
|
|
Height |
177.0mm (7") |
107.0mm (4.2") |
Width |
423.0mm (16.7") |
621.0mm (24.4") |
Depth |
281.0mm (11.1") |
142.0mm (5.6") |
Weight |
8.18kg (18lbs) |
6.36kg (14lbs) |
Enclosure |
Bass Reflex |
Bass Reflex |
Finish |
MDF/Lacquer |
n/a |
Available Colors |
White |
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 |