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MartinLogan Installer Series IW5-LCR vs Definitive UIW RLS III Comparison

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MartinLogan Installer Series IW5-LCR

Passive In-wall | 60-20kHz

MartinLogan Installer Series IW5-LCR
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Definitive UIW RLS III

Passive In-wall | 24-30kHz

Definitive Technology UIW RLS III
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MartinLogan Installer Series IW5-LCR MartinLogan Installe...
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Definitive UIW RLS III Definitive UIW RLS I...
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MartinLogan Installer Series IW5-LCR vs Definitive UIW RLS III Speaker Comparison

In this review, we will be comparing Installer Series IW5-LCR and UIW RLS III, two Passive In-wall speakers from MartinLogan and Definitive Technology.

Let's have a brief look at the main features of MartinLogan Installer Series IW5-LCR and Definitive UIW RLS III first before getting into our more detailed comparison.

MartinLogan Installer Series IW5-LCR Key Specs

  • 2-way Design
  • 0.75" Hard-Dome Tweeter
  • 2 x 5.5" Mineral-filled poly Woofer
  • 60-20kHz Frequency Response
  • 89 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:15-70watts
  • Dimensions (H x W x D): 210.0" x 11.6250" x 3.0000"( 210.0 x 296.0 x 77.0mm )

Definitive UIW RLS III Key Specs

  • 2-way Design
  • 1" Hard-Dome Tweeter
  • 2 x 5.25" Polypropylene Woofer
  • 24-30kHz Frequency Response
  • 92 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:10-325watts
  • Dimensions (H x W x D): 604.0" x 5.8750" x 3.8750"( 604.0 x 150.0 x 99.0mm )

What size room are the MartinLogan Installer Series IW5-LCR and Definitive UIW RLS III 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 Installer Series IW5-LCR Definitive UIW RLS III
Near-field Good Are you nuts?
Small Room Good Bad
Mid-size Room Average Poor
Large Room Poor Good
Very Large Room No way Good

(* 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 Installer Series IW5-LCR and Definitive UIW RLS III 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 Installer Series IW5-LCR and UIW RLS III are 2-way speakers.

Driver MartinLogan Installer Series IW5-LCR Definitive UIW RLS III
Driver Setup 2-way 2-way
Tweeter 0.75-inch 1-inch
Midrange - -
Woofer 2 x 5.5-inch 2 x 5.25-inch

Installer Series IW5-LCR features a 0.75" Hard-Dome Tweeter and 2 x 5.5" Mineral-filled poly Woofer . On the other hand, the UIW RLS III features a 1" Hard-Dome Tweeter and 2 x 5.25" Polypropylene Woofer .

Frequency Response

Installer Series IW5-LCR has a frequency range of 60-20kHz whereas UIW RLS III has a frequency range of 24-30kHz. With a minimum frequency of 24Hz, the UIW RLS III can go significantly deeper on the low side and provide stronger bass compared to the Installer Series IW5-LCR's min frequency of 60Hz.

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

Installer Series IW5-LCR
UIW RLS III
Min
Average
Max
High Frequency

In-wall Speakers

MartinLogan Installer Series IW5-LCR
Definitive UIW RLS III
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

Installer Series IW5-LCR and UIW RLS III have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Installer Series IW5-LCR sensitivity is rated at 89 dB and the UIW RLS III's is at 92 dB. This 3 dB difference makes the Definitive UIW RLS III a more sensitive speaker compared to MartinLogan Installer Series IW5-LCR, hence will play louder with the same amount of watts.

Sensitivity

In-wall Speakers

Installer Series IW5-LCR
UIW RLS III
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.

Installer Series IW5-LCR can handle a max power of 325 watts RMS from the amp the whereas Installer Series IW5-LCR has a max power handling value of 70 watts RMS , 255 watts less than the UIW RLS 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

Installer Series IW5-LCR features Spring post type posts and UIW RLS III 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 MartinLogan Installer Series IW5-LCR's and Definitive UIW RLS III's external dimensions. MartinLogan Installer Series IW5-LCR has external dimensions of 210.0 x 296.0 x 77.0mm ( 8.2500-inch x 11.6250-inch x 3.0000-inch) whereas Definitive UIW RLS III has external dimensions of 604.0 x 150.0 x 99.0mm ( 23.7500-inch x 5.8750-inch x 3.8750-inch) .

MartinLogan Installer Series IW5-LCR is 394mm shorter and 22mm less deeper than Definitive UIW RLS III but it is also 146mm wider.

What's in the Box of MartinLogan Installer Series IW5-LCR?

Here are the items that are included inside the box of Installer Series IW5-LCR:
  • In-wall loudspeaker
  • Grille
  • User-feets Manual
  • Cutout Template
  • What's in the Box of Definitive UIW RLS III?

    Here are the items that come with the UIW RLS III:
  • In-wall loudspeaker
  • Grille
  • Self-adhesive foam gasket
  • Paint mask
  • Wall-Mount Template
  • Owners Manual
  • Online Product Registration Card

  • Reasons to choose MartinLogan Installer Series IW5-LCR over Definitive Technology UIW RLS III
    Woofer Size 5.5 inches vs 5.25 inches Larger woofer
    Height 210mm vs 604mm Easier to fit in smaller spaces
    Price per pair* 760USD vs 1398USD costs less (*prices may change depending on the seller, location and time)

    Reasons to choose Definitive Technology UIW RLS III over MartinLogan Installer Series IW5-LCR

    Max Input Power 325 watts vs 70 watts Handle more power from your amplifier
    Sensitivity 92 dB vs 89 dB Play louder with same amount of amplification power
    Low Frequency Response 24 Hz vs 60 Hz Generates deeper bass
    High Frequency Response 30k Hz vs 20k Hz Generates higher frequency
    Passive Radiator 2 x 5.25-inch vs None Increases the bass performance
    Base Surface Area 148cm2 vs 227cm2 Takes less floor space
    MartinLogan Installer Series IW5-LCR vs Definitive UIW RLS III Specs Table
    Detailed comparison of specifications
    General MartinLogan Installer Series IW5-LCR Definitive Technology UIW RLS III
    Brand MartinLogan Definitive Technology
    Speaker Type Passive In-wall Speaker Passive In-wall Speaker
    Power Range 15-70 watts 10-325 watts
    Sensitivity 89 dB 92 dB
    Impedance 8 ohms 8 ohms
    Frequency Response 60-20kHz 24-30kHz
    Drivers
    Woofer Quantity 2 2
    Woofer Size 5.5" 5.25"
    Woofer Composition Mineral-filled poly Polypropylene
    Woofer Surround Material Rubber Butyl Rubber
    Tweeter Size 0.75" 1"
    Tweeter Type Hard-Dome Hard-Dome
    Aimable Tweeter No No
    Midrange Driver N/A" N/A"
    Physical Specs
    Height 210.0mm (8.3") 604.0mm (23.8")
    Width 296.0mm (11.7") 150.0mm (5.9")
    Depth 77.0mm (3") 99.0mm (3.9")
    Enclosure In-wall In-wall
    Moisture Resistancy No Yes
    Connections
    Biamp Inputs No No
    Other
    Parts Warranty 5 Yrs w/ Registration 5 Years
    Labor Warranty 5 Yrs w/ Registration 5 Years

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