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MartinLogan Axis vs Definitive UIW RLS II Comparison

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MartinLogan Axis

Passive In-wall | 45-25kHz

MartinLogan Axis
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Definitive UIW RLS II

Passive In-wall | 22-30kHz

Definitive Technology UIW RLS II
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MartinLogan Axis MartinLogan Axis
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Definitive UIW RLS II Definitive UIW RLS I...
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MartinLogan Axis vs Definitive UIW RLS II Speaker Comparison

In this review, we will be comparing Axis and UIW RLS II, two Passive In-wall speakers from MartinLogan and Definitive Technology.

Let's have a brief look at the main features of MartinLogan Axis and Definitive UIW RLS II first before getting into our more detailed comparison.

MartinLogan Axis Key Specs

  • 2-way Design
  • 1.25x2.4" Folded Motion Ribbon Tweeter
  • 2 x 5.25" Aluminum Woofer
  • 45-25kHz Frequency Response
  • 94 dB Sensitivity
  • Impedance: 4ohms
  • Power Range:20-250watts
  • Dimensions (H x W x D): 367.0" x 7.1250" x 3.7500"( 367.0 x 181.0 x 96.0mm )

Definitive UIW RLS II Key Specs

  • 2-way Design
  • 1" Hard-Dome Tweeter
  • 2 x 6.5" Polypropylene Woofer
  • 22-30kHz Frequency Response
  • 92 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:10-350watts
  • Dimensions (H x W x D): 724.0" x 7.0000" x 3.8750"( 724.0 x 178.0 x 99.0mm )

What size room are the MartinLogan Axis and Definitive UIW RLS II 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 Axis Definitive UIW RLS II
Near-field Poor Are you nuts?
Small Room Poor Bad
Mid-size Room Good Poor
Large Room Good Good
Very Large Room Average 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 Axis and Definitive UIW RLS II 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 Axis and UIW RLS II are 2-way speakers.

Driver MartinLogan Axis Definitive UIW RLS II
Driver Setup 2-way 2-way
Tweeter 1.25x2.4-inch 1-inch
Midrange - -
Woofer 2 x 5.25-inch 2 x 6.5-inch

Axis features a 1.25x2.4" Folded Motion Ribbon Tweeter and 2 x 5.25" Aluminum Woofer . On the other hand, the UIW RLS II features a 1" Hard-Dome Tweeter and 2 x 6.5" Polypropylene Woofer .

Frequency Response

Axis has a frequency range of 45-25kHz whereas UIW RLS II has a frequency range of 22-30kHz. With a minimum frequency of 22Hz, the UIW RLS II can go significantly deeper on the low side and provide stronger bass compared to the Axis's min frequency of 45Hz.

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

Axis
UIW RLS II
Min
Average
Max
High Frequency

In-wall Speakers

MartinLogan Axis
Definitive UIW RLS II
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

Axis is a 4 ohms speaker compared to the UIW RLS II 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 Axis can provide this impedance level.

These two speakers also have different sensitivity levels. Axis sensitivity is rated at 94 dB and the UIW RLS II's is rated at 92 dB. This 2 dB difference makes the MartinLogan Axis a more sensitive speaker compared to Definitive UIW RLS II, hence will play louder with the same amount of watts.

Sensitivity

In-wall Speakers

Axis
UIW RLS II
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.

Axis can handle a max power of 350 watts RMS from the amp the whereas Axis has a max power handling value of 250 watts RMS , 100 watts less than the UIW RLS II.

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

Axis features Spring post type posts and UIW RLS II 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 Axis's and Definitive UIW RLS II's external dimensions. MartinLogan Axis has external dimensions of 367.0 x 181.0 x 96.0mm ( 14.4375-inch x 7.1250-inch x 3.7500-inch) whereas Definitive UIW RLS II has external dimensions of 724.0 x 178.0 x 99.0mm ( 28.5000-inch x 7.0000-inch x 3.8750-inch) .

MartinLogan Axis is 357mm shorter and 3mm less deeper than Definitive UIW RLS II but it is also 3mm wider.

What's in the Box of MartinLogan Axis?

Here are the items that are included inside the box of Axis:
  • In-wall speaker
  • Grille
  • Paint shield
  • User-feets Manual
  • Install Template
  • What's in the Box of Definitive UIW RLS II?

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

  • Reasons to choose MartinLogan Axis over Definitive Technology UIW RLS II
    Sensitivity 94 dB vs 92 dB Play louder with same amount of amplification power
    Height 367mm vs 724mm Easier to fit in smaller spaces
    Base Surface Area 173cm2 vs 176cm2 Takes less floor space

    Reasons to choose Definitive Technology UIW RLS II over MartinLogan Axis

    Max Input Power 350 watts vs 250 watts Handle more power from your amplifier
    Nominal Impedance 8 ohms vs 4 ohms Less selective with amplifiers
    Woofer Size 6.5 inches vs 5.25 inches Larger woofer
    Low Frequency Response 22 Hz vs 45 Hz Generates deeper bass
    High Frequency Response 30k Hz vs 25k Hz Generates higher frequency
    Passive Radiator 2 x 6.5-inch vs None Increases the bass performance
    Price per pair* 1998USD vs 2600USD costs less (*prices may change depending on the seller, location and time)
    MartinLogan Axis vs Definitive UIW RLS II Specs Table
    Detailed comparison of specifications
    General MartinLogan Axis Definitive Technology UIW RLS II
    Brand MartinLogan Definitive Technology
    Speaker Type Passive In-wall Speaker Passive In-wall Speaker
    Power Range 20-250 watts 10-350 watts
    Sensitivity 94 dB 92 dB
    Impedance 4 ohms 8 ohms
    Frequency Response 45-25kHz 22-30kHz
    Drivers
    Woofer Quantity 2 2
    Woofer Size 5.25" 6.5"
    Woofer Composition Aluminum Polypropylene
    Woofer Surround Material Rubber Butly Rubber
    Tweeter Size 1.25x2.4" 1"
    Tweeter Type Folded Motion Ribbon Hard-Dome
    Aimable Tweeter No No
    Midrange Driver N/A" N/A"
    Physical Specs
    Height 367.0mm (14.4") 724.0mm (28.5")
    Width 181.0mm (7.1") 178.0mm (7")
    Depth 96.0mm (3.8") 99.0mm (3.9")
    Enclosure In-wall In-wall
    Moisture Resistancy No Yes
    Connections
    Biamp Inputs No No
    Other
    Parts Warranty 5 Years w/registration 5 Years
    Labor Warranty 5 Years w.registration 5 Years

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