In this review, we will be comparing Motion XT C100 and Q650c, two Passive Center Channel speakers from MartinLogan and KEF.
Let's have a brief look at the main features
of MartinLogan Motion XT C100 and KEF Q650c first before getting into our more
detailed comparison.
MartinLogan Motion XT C100 Key Specs
- 2-way Design
- 1.25 x 2.4" Folded Motion XT Tweeter
- 2 x 6.5" Aluminum Woofer
- 42-25k Hz Frequency Response
- 93 dB Sensitivity
- Impedance: 5ohms
- Power Range:20-300watts
- Weight:15.40kg
- Dimensions (H x W x D): 203.0" x 24" x 14-1/2"( 203 x 610 x 368mm )
KEF Q650c Key Specs
- 2-way Design
- 11th Generation Uni-Q Driver
- 1" Dome Tweeter
- 2 x 6.5" aluminum Woofer
- 64-28k Hz Frequency Response
- 87 dB Sensitivity
- Impedance: 8ohms
- Power Range:15-150watts
- Weight:13.64kg
- Dimensions (H x W x D): 212.0" x 24-13/16" x 11-15/16"( 212.0 x 631.0 x 304.0mm )
What size room are the MartinLogan Motion XT C100 and KEF Q650c 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* |
MartinLogan Motion XT C100 |
KEF Q650c |
| Near-field |
Poor |
Poor |
| Small Room |
Poor |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Good |
Average |
| Very Large Room |
Average |
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 MartinLogan Motion XT C100 and KEF Q650c 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 Motion XT C100 and Q650c are 2-way speakers.
| Driver |
MartinLogan Motion XT C100 |
KEF Q650c |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1.25 x 2.4-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
Motion XT C100 features a 1.25 x 2.4" Folded Motion XT Tweeter and 2 x 6.5" Aluminum Woofer with a Crossover frequency at 1300Hz and 2500Hz. On the other hand, the Q650c features a 1" vented aluminum Dome Tweeter and 2 x 6.5" aluminum Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Motion XT C100 has a frequency range of 42-25k Hz whereas Q650c has a frequency range of 64-28k Hz. With a minimum frequency of 42Hz, the Motion XT C100 can go significantly deeper on the low side and provide stronger bass compared to the Q650c's min frequency of 64Hz.
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
MartinLogan Motion XT C100
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 XT C100 is a 5 ohms speaker compared to the Q650c which has a nominal impedance of 8 ohms.
These two speakers also have different sensitivity levels. Motion XT C100 sensitivity is rated at 93 dB and the Q650c's is rated at 87 dB. This 6 dB difference makes the MartinLogan Motion XT C100 a more sensitive speaker compared to KEF Q650c, 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.
Motion XT C100 can handle a max power of 300 watts RMS from the amp the whereas Q650c has a max power handling value of 150 watts RMS, 150 watts less than the Motion XT C100.
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 XT C100 features Custom 5-way bi-wire tool-less binding posts posts which make bi-amping or bi-wiring possible. Q650c has a Binding post which doesn't feature bi-amping/bi-wiring.
MartinLogan Motion XT C100's Custom 5-way bi-wire tool-less binding posts terminals allows Bi-amping or bi-wiring
KEF Q650c's Binding 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 MartinLogan Motion XT C100's and KEF Q650c's external dimensions. MartinLogan Motion XT C100 has external dimensions of 203 x 610 x 368mm ( 8inch x 24inch x 14-1/2inch ) whereas KEF Q650c has external dimensions of 212.0 x 631.0 x 304.0mm ( 8-5/16 x 24-13/16 x 11-15/16inch) .
MartinLogan Motion XT C100 is 21mm narrower and 9mm shorter than KEF Q650c but it is also 64mm deeper.
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 Motion XT C100 is approximately 2244.8cm2 / 347.9inch2 and base area of the KEF Q650c is approximately 1918.2cm2 / 297.3inch2. The Motion XT C100 requires 17% more surface area than the Q650c which gives it a small disadvantage on placement in tight spaces.