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Definitive UIW RSS III vs MartinLogan Motion CI MW4-LCR Comparison

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Definitive UIW RSS III

Passive In-wall | 40-30kHz

Definitive Technology UIW RSS III
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MartinLogan Motion CI MW4-LCR

Passive In-wall | 78-25kHz

MartinLogan Motion CI MW4-LCR
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Definitive UIW RSS III Definitive UIW RSS I...
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MartinLogan Motion CI MW4-LCR MartinLogan Motion C...
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Definitive UIW RSS III vs MartinLogan Motion CI MW4-LCR Speaker Comparison

In this review, we will be comparing UIW RSS III and Motion CI MW4-LCR, two Passive In-wall speakers from Definitive Technology and MartinLogan.

Let's have a brief look at the main features of Definitive UIW RSS III and MartinLogan Motion CI MW4-LCR first before getting into our more detailed comparison.

Definitive UIW RSS III Key Specs

  • 2-way Design
  • 1" Hard-Dome Tweeter
  • 2 x 3.5" Polypropylene Woofer
  • 40-30kHz Frequency Response
  • 90 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:10-200watts
  • Dimensions (H x W x D): 251.0" x 8.3750" x 3.8750"( 251.0 x 213.0 x 99.0mm )

MartinLogan Motion CI MW4-LCR Key Specs

  • 2-way Design
  • 1" Folded Motion Ribbon Tweeter
  • 2 x 4" Fiberglass Woofer
  • 78-25kHz Frequency Response
  • 93 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:50-100watts
  • Dimensions (H x W x D): 134.0" x 11.8750" x 2.6875"( 134.0 x 302.0 x 69.0mm )

What size room are the Definitive UIW RSS III and MartinLogan Motion CI MW4-LCR 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* Definitive UIW RSS III MartinLogan Motion CI MW4-LCR
Near-field Poor Average
Small Room Average Good
Mid-size Room Good Average
Large Room Average Poor
Very Large Room Poor Bad

(* 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 Definitive UIW RSS III and MartinLogan Motion CI MW4-LCR 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 UIW RSS III and Motion CI MW4-LCR are 2-way speakers.

Driver Definitive UIW RSS III MartinLogan Motion CI MW4-LCR
Driver Setup 2-way 2-way
Tweeter 1-inch 1-inch
Midrange - -
Woofer 2 x 3.5-inch 2 x 4-inch

UIW RSS III features a 1" Hard-Dome Tweeter and 2 x 3.5" Polypropylene Woofer . On the other hand, the Motion CI MW4-LCR features a 1" Folded Motion Ribbon Tweeter and 2 x 4" Fiberglass Woofer .

Frequency Response

UIW RSS III has a frequency range of 40-30kHz whereas Motion CI MW4-LCR has a frequency range of 78-25kHz. With a minimum frequency of 40Hz, the UIW RSS III can go significantly deeper on the low side and provide stronger bass compared to the Motion CI MW4-LCR's min frequency of 78Hz.

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 In-wall class in our database.

Low Frequency

In-wall Speakers

UIW RSS III
Motion CI MW4-LCR
Min
Average
Max
High Frequency

In-wall Speakers

Definitive UIW RSS III
MartinLogan Motion CI MW4-LCR
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

UIW RSS III and Motion CI MW4-LCR have the same Impedance of 8 ohms but where they differ is the sensitivity levels. UIW RSS III sensitivity is rated at 90 dB and the Motion CI MW4-LCR's is at 93 dB. This 3 dB difference makes the MartinLogan Motion CI MW4-LCR a more sensitive speaker compared to Definitive UIW RSS III, hence will play louder with the same amount of watts.

Sensitivity

In-wall Speakers

UIW RSS III
Motion CI MW4-LCR
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.

UIW RSS III can handle a max power of 200 watts RMS from the amp the whereas Motion CI MW4-LCR has a max power handling value of 100 watts RMS, 100 watts less than the UIW RSS III.

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

UIW RSS III features Spring post type posts and Motion CI MW4-LCR has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.

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 Definitive UIW RSS III's and MartinLogan Motion CI MW4-LCR's external dimensions. Definitive UIW RSS III has external dimensions of 251.0 x 213.0 x 99.0mm ( 9.8750-inch x 8.3750-inch x 3.8750-inch) whereas MartinLogan Motion CI MW4-LCR has external dimensions of 134.0 x 302.0 x 69.0mm ( 5.2500-inch x 11.8750-inch x 2.6875-inch) .

MartinLogan Motion CI MW4-LCR is 117mm shorter and 30mm less deeper than Definitive UIW RSS III but it is also 89mm wider.

What's in the Box of Definitive UIW RSS III?

Here are the items that are included inside the box of UIW RSS III:
  • In-wall/In-cieling bipolar speaker
  • Grille
  • 7 Foam strips
  • 2 Screws
  • Paint mask
  • Wall template
  • Owners Manual
  • Online Product Registration Card
  • What's in the Box of MartinLogan Motion CI MW4-LCR?

    Here are the items that come with the Motion CI MW4-LCR:
  • In-wall loudspeaker
  • Grille
  • Torx-bit
  • User-feets Manual
  • Cutout Template

  • Reasons to choose Definitive Technology UIW RSS III over MartinLogan Motion CI MW4-LCR
    Max Input Power 200 watts vs 100 watts Handle more power from your amplifier
    Low Frequency Response 40 Hz vs 78 Hz Generates deeper bass
    High Frequency Response 30k Hz vs 25k Hz Generates higher frequency
    Passive Radiator 2 x 3.5-inch vs None Increases the bass performance
    Price per pair* 1098USD vs 1100USD costs less (*prices may change depending on the seller, location and time)

    Reasons to choose MartinLogan Motion CI MW4-LCR over Definitive Technology UIW RSS III

    Sensitivity 93 dB vs 90 dB Play louder with same amount of amplification power
    Woofer Size 4 inches vs 3.5 inches Larger woofer
    Height 134mm vs 251mm Easier to fit in smaller spaces
    Base Surface Area 208cm2 vs 210cm2 Takes less floor space
    Definitive UIW RSS III vs MartinLogan Motion CI MW4-LCR Specs Table
    Detailed comparison of specifications
    General Definitive Technology UIW RSS III MartinLogan Motion CI MW4-LCR
    Brand Definitive Technology MartinLogan
    Speaker Type Passive In-wall Speaker Passive In-wall Speaker
    Power Range 10-200 watts 50-100 watts
    Sensitivity 90 dB 93 dB
    Impedance 8 ohms 8 ohms
    Frequency Response 40-30kHz 78-25kHz
    Drivers
    Woofer Quantity 2 2
    Woofer Size 3.5" 4"
    Woofer Composition Polypropylene Fiberglass
    Woofer Surround Material Butyl Rubber Rubber
    Tweeter Size 1" 1"
    Tweeter Type Hard-Dome Folded Motion Ribbon
    Aimable Tweeter No No
    Midrange Driver N/A" N/A"
    Physical Specs
    Height 251.0mm (9.9") 134.0mm (5.3")
    Width 213.0mm (8.4") 302.0mm (11.9")
    Depth 99.0mm (3.9") 69.0mm (2.7")
    Enclosure In-wall In-wall
    Moisture Resistancy Yes No
    Connections
    Biamp Inputs No No
    Other
    Parts Warranty 5 Years 5 Years
    Labor Warranty 5 Years 5 Years

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