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MartinLogan Motion SLM X3 vs MartinLogan 6i Comparison

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MartinLogan Motion SLM X3

Passive On-wall | 120-25k Hz

MartinLogan Motion SLM X3
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MartinLogan 6i

Passive Center Channel | 120-23k Hz

MartinLogan Motion 6i
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MartinLogan Motion SLM X3 MartinLogan Motion S...
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MartinLogan 6i MartinLogan 6i
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MartinLogan Motion S...
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MartinLogan 6i
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MartinLogan Motion SLM X3 vs MartinLogan 6i Speaker Comparison

In this review, we will be comparing two different type of speakers by MartinLogan. MartinLogan Motion SLM X3 is a On-wall speaker whereas the Motion 6i is a Center Channel speaker.

Let's have a brief look at the main features of MartinLogan Motion SLM X3 and MartinLogan 6i first before getting into our more detailed comparison.

MartinLogan Motion SLM X3 Key Specs

  • 2-way Design
  • " AMT Tweeter
  • 6 x 4" Aluminium Woofer
  • 120-25k Hz Frequency Response
  • 93 dB Sensitivity
  • Impedance: 4ohms
  • Power Range:20-140watts
  • Weight:5.90kg
  • Dimensions (H x W x D): 6-3/8" x 48-1/16" x 2" ( 162.0 x 1220.0 x 51.0mm )

MartinLogan 6i Key Specs

  • 2-way Design
  • 1.0 x 1.0" Folded Motion Tweeter
  • 2 x 3.5" poly cone woofers with rigid dust caps Woofer
  • 120-23k Hz Frequency Response
  • 89 dB Sensitivity
  • Impedance: 6ohms
  • Power Range:20-130watts
  • Weight:2.59kg
  • Dimensions (H x W x D): 5-1/4" x 17-1/2" x 4" ( 134.0 x 445.0 x 102.0mm )

Motion SLM X3 and Motion 6i are members of MartinLogan's Motion series of speakers. Below you can find the loudspeakers from this series.

MartinLogan Motion Series History
Model Body Frequency SensitivityImpedance Woofer
MartinLogan 60XTi
  
Floor-standing 35-25k Hz 94 dB4Ω 2 x 8"
MartinLogan 15i
  
Bookshelf 60-25k Hz 92 dB5Ω 1 x 5.25"
MartinLogan 35XTi
  
Bookshelf 50-25k Hz 92 dB4Ω 1 x 6.5"
MartinLogan 40i
  
Floor-standing 40-25k Hz 92 dB4Ω 2 x 6.5"
MartinLogan 50XTi
  
Center Channel 50-25k Hz 94 dB4Ω 2 x 6.5"
MartinLogan 20i
  
Floor-standing 46-25k Hz 90 dB4Ω 2 x 5.5"
MartinLogan LX16
  
Bookshelf 60-25k Hz 92 dB5Ω 1 x 5.25"
MartinLogan 30i
  
Center Channel 65-25k Hz 91 dB4Ω 1 x 5.25"
MartinLogan 6i
Center Channel 120-23k Hz 89 dB6Ω 2 x 3.5"
MartinLogan 8i
  
Center Channel 70-23k Hz 89 dB4Ω 2 x 4"

What size room are the MartinLogan Motion SLM X3 and MartinLogan 6i 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 SLM X3 MartinLogan 6i
Near-field Good Poor
Small Room Good Average
Mid-size Room Average Good
Large Room Poor Average
Very Large Room No way 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 SLM X3 and MartinLogan 6i 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 Motion SLM X3 and Motion 6i are 2-way speakers.

Driver MartinLogan Motion SLM X3 MartinLogan 6i
Driver Setup 2-way 2-way
Tweeter -inch 1.0 x 1.0-inch
Midrange - -
Woofer 6 x 4-inch 2 x 3.5-inch

Motion SLM X3 features a " Folded Motion AMT Tweeter and 6 x 4" Aluminium Woofer with a Crossover frequency at 3,000 Hz. On the other hand, the Motion 6i features a 1.0 x 1.0" Folded Motion Tweeter and 2 x 3.5" poly cone woofers with rigid dust caps Woofer .

Frequency Response

Motion SLM X3 has a frequency range of 120-25k Hz whereas Motion 6i has a frequency range of 120-23k Hz.

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 On-wall class in our database.

Low Frequency

On-wall Speakers

Motion SLM X3
Motion 6i
Min
Average
Max
High Frequency

On-wall Speakers

MartinLogan Motion SLM X3
MartinLogan 6i
Min
Average
Max

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 SLM X3 is a 4 ohms speaker compared to the Motion 6i which has a nominal impedance of 6 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 SLM X3 can provide this impedance level.

These two speakers also have different sensitivity levels. Motion SLM X3 sensitivity is rated at 93 dB and the Motion 6i's is rated at 89 dB. This 4 dB difference makes the MartinLogan Motion SLM X3 a more sensitive speaker compared to MartinLogan 6i, hence will play louder with the same amount of watts.

Sensitivity

On-wall Speakers

Motion SLM X3
Motion 6i
Min
Average
Max

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 SLM X3 can handle a max power of 140 watts RMS from the amp the whereas Motion 6i has a max power handling value of 130 watts RMS, 10 watts less than the Motion SLM X3.

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 SLM X3 features Spring post type posts and Motion 6i has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.

MartinLogan 6i Terminals
MartinLogan 6i's Spring 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 SLM X3's and MartinLogan 6i's external dimensions. MartinLogan Motion SLM X3 has external dimensions of 162.0 x 1220.0 x 51.0mm ( 6-3/8 x 48-1/16 x 2inch) whereas MartinLogan 6i has external dimensions of 134.0 x 445.0 x 102.0mm ( 5-1/4 x 17-1/2 x 4inch) .

MartinLogan 6i is 775mm narrower and 28mm shorter than MartinLogan Motion SLM X3 but it is also 51mm 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 SLM X3 is approximately 622.2cm2 / 96.4inch2 and base area of the MartinLogan 6i is approximately 453.9cm2 / 70.4inch2. The Motion SLM X3 requires 37% more surface area than the Motion 6i which gives it a small disadvantage on placement in tight spaces.

What's in the Box of MartinLogan 6i?

Here are the items that come with the Motion 6i:
  • LCR loudspeaker
  • Grille
  • 2 Wall-bracket
  • 2 Shoulder bolts
  • 4 Rubber bumpers
  • Cleaning cloth
  • User-feets Manual (En/Fr)
  • Installation template
  • Product Registration Card


Reasons to choose MartinLogan Motion SLM X3 over MartinLogan Motion 6i
Max Input Power 140 watts vs 130 watts Handle more power from your amplifier
Sensitivity 93 dB vs 89 dB Play louder with same amount of amplification power
Woofer Size 4 inches vs 3.5 inches Larger woofer
Number of Woofers 6 vs 2 More woofers
High Frequency Response 25k Hz vs 23k Hz Generates higher frequency

Reasons to choose MartinLogan Motion 6i over MartinLogan Motion SLM X3

Nominal Impedance 6 ohms vs 4 ohms Less selective with amplifiers
Height 134mm vs 162mm Easier to fit in smaller spaces
Base Surface Area 453cm2 vs 622cm2 Takes less floor space
Price per pair* 300USD vs 1300USD costs less (*prices may change depending on the seller, location and time)
MartinLogan Motion SLM X3 vs MartinLogan 6i Specs Table
Detailed comparison of specifications
General MartinLogan Motion SLM X3 MartinLogan Motion 6i
Brand MartinLogan MartinLogan
Speaker Type On-Wall speakers Center channel speaker
Power Range 20-140 watts 20-130 watts
Sensitivity 93 dB 89 dB
Impedance 4 ohms 6 ohms
Frequency Response 120-25k Hz 120-23k Hz
Drivers
Woofer Quantity 6 2
Woofer Size 4" 3.5"
Woofer Composition Aluminium poly cone woofers with rigid dust caps
Tweeter Size - 1.0 x 1.0"
Tweeter Type AMT Folded Motion
Aimable Tweeter No No
Midrange Driver No No
Crossover Frequency 3,000 Hz n/a
Suggested Break-in Period n/a Allow 72 hours of break-in at 90 dB
Physical Specs
Height 162.0mm (6.4") 134.0mm (5.3")
Width 1220.0mm (48") 445.0mm (17.5")
Depth 51.0mm (2") 102.0mm (4")
Weight 5.90kg (13lbs) 2.59kg (5.7lbs)
Enclosure Bass Reflex Passive Radiator
Available Colors n/a Gloss Black, Matt White, Red Walnut
Grille Yes Yes
Moisture Resistancy No No
Connections
Biamp Inputs No n/a
Other
Parts Warranty 5 Yrs w/ Registration
Labor Warranty 5 Yrs w/ Registration

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