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Q Acoustics M40 vs KEF LS50 Wireless II Comparison

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Q Acoustics M40

Powered Floor-standing | 38-22k Hz

Q Acoustics M40
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KEF LS50 Wireless II

Powered Bookshelf | 45-28k Hz

KEF LS50 Wireless II
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Q Acoustics M40 Q Acoustics M40
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KEF LS50 Wireless II KEF LS50 Wireless II
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Q Acoustics M40
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KEF LS50 Wireless II
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Q Acoustics M40 vs KEF LS50 Wireless II Speaker Comparison

In this review, we will be comparing two different type of speakers . Q Acoustics M40 is a Floor-standing speaker whereas the LS50 Wireless II is a Bookshelf speaker.

Let's have a brief look at the main features of Q Acoustics M40 and KEF LS50 Wireless II first before getting into our more detailed comparison.

Q Acoustics M40 Key Specs

  • 2-way Design
  • 50-watt RMS( 100-watt Peak) Integrated Amplifier
  • 0.875" Dome Tweeter
  • 2 x 5" Woofer
  • 38-22k Hz Frequency Response
  • 24-bit Max Depth / 192 kHz Max Sample Rate
  • Built-in 5.0 Bluetooth
  • Weight:11.80kg
  • Dimensions (H x W x D): 710.0" x 10" x 11.7"( 250 x 710 x 296 mm )

KEF LS50 Wireless II Key Specs

  • 2-way Design
  • 380-watt RMS( 760-watt Peak) Integrated Amplifier
  • 12th Generation Uni-Q Driver
  • 1" Hard-Dome Tweeter
  • 5.25" Aluminum Woofer
  • 45-28k Hz Frequency Response
  • 32-bit Max Depth / 384 kHz Max Sample Rate
  • Built-in 4.2 Bluetooth
  • App Control Feature
  • Weight:10.00kg
  • Dimensions (H x W x D): 277.8" x 7.875" x 12.6875"( 277.8 x 200.0 x 322.3mm )

In the following sections, we will get into more detail in order to better understand how the Q Acoustics M40 and KEF LS50 Wireless 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 M40 and LS50 Wireless II are 2-way speakers.

Driver Q Acoustics M40 KEF LS50 Wireless II
Driver Setup 2-way 2-way
Tweeter 0.875-inch 1-inch
Midrange - -
Woofer 2 x 5-inch 1 x 5.25-inch

M40 features a 0.875" Dome Tweeter and 2 x 5" Woofer . On the other hand, the LS50 Wireless II features a 1" Aluminum Hard-Dome Tweeter and 1 x 5.25" Aluminum Woofer .

Frequency Response

M40 has a frequency range of 38-22k Hz whereas LS50 Wireless II has a frequency range of 45-28k Hz. With a minimum frequency of 38Hz, the M40 can go significantly deeper on the low side and provide stronger bass compared to the LS50 Wireless II'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 Floor-standing class in our database.

Low Frequency

Floor-standing Speakers

M40
LS50 Wireless II
Min
Average
Max
High Frequency

Floor-standing Speakers

Q Acoustics M40
KEF LS50 Wireless 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.

Cabinet Type and Port Position

Both M40 and LS50 Wireless II have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.

If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.

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 Q Acoustics M40's and KEF LS50 Wireless II's external dimensions. Q Acoustics M40 has external dimensions of 250 x 710 x 296 mm ( 10 x 28 x 11.7 inch) whereas KEF LS50 Wireless II has external dimensions of 277.8 x 200.0 x 322.3mm ( 10.9375 x 7.875 x 12.6875inch) .

KEF LS50 Wireless II is 50mm narrower and 432.2mm shorter than Q Acoustics M40 but it is also 26.3mm 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 Q Acoustics M40 is approximately 740.0cm2 / 114.7inch2 and base area of the KEF LS50 Wireless II is approximately 644.6cm2 / 99.9inch2. The M40 requires 15% more surface area than the LS50 Wireless II which gives it a small disadvantage on placement in tight spaces.

What's in the Box of Q Acoustics M40?

Here are the items that are included inside the box of M40:
  • 1x Powered M40 speaker
  • 1x Passive M40 speaker
  • 4x Rear Stabiliser
  • 8x M5 screw
  • 8x Spike Feet
  • 8x Spike Cover
  • 1x Remote Handset (including batteries)
  • 1x Speaker Cable (4 metres)
  • 1x UK Power Cord (2 metres)
  • 1x EU Power Cord (2 metres)
  • 2x Foam Bungs
  • What's in the Box of KEF LS50 Wireless II?

    Here are the items that come with the LS50 Wireless II:
  • 2 Wireless powered speakers
  • Two 6.5-feet AC power cords
  • 10-feet Cat-6 interconnect speaker cable
  • Remote control
  • 2 AAA batteries
  • Quick Start Guide
  • Important Safety Information
  • Warranty Information

  • Reasons to choose Q Acoustics M40 over KEF LS50 Wireless II
    Number of Woofers 2 vs 1 More woofers
    Low Frequency Response 38 Hz vs 45 Hz Generates deeper bass
    Price per pair* 999USD vs 2499USD costs less (*prices may change depending on the seller, location and time)
    RCA Connection Yes vs No Connection via RCA input

    Reasons to choose KEF LS50 Wireless II over Q Acoustics M40

    Woofer Size 5.25 inches vs 5 inches Larger woofer
    High Frequency Response 28k Hz vs 22k Hz Generates higher frequency
    App-Based Control Apple iOS, Android vs None Control the speaker via an app
    Height 277mm vs 710mm Easier to fit in smaller spaces
    Base Surface Area 644cm2 vs 740cm2 Takes less floor space
    Ethernet Connection Yes vs No High quality streaming over Ethernet
    HDMI Input eARC vs No Connect HDMI sources directly
    Q Acoustics M40 vs KEF LS50 Wireless II Specs Table
    Detailed comparison of specifications
    General Q Acoustics M40 KEF LS50 Wireless II
    Brand Q Acoustics KEF
    Speaker Type Powered stereo speakers Powered Stereo Speakers
    Frequency Response 38-22k Hz 45-28k Hz
    Amplifier
    Watts RMS (Continuous) 50-watt RMS 380-watt RMS
    Watts Peak (Max) 100-watt RMS 760-watt RMS
    Max Bit Depth 24-bit 32-bit
    Max Sample Rate 192 kHz 384 kHz
    Drivers
    Woofer Quantity 2 1
    Woofer Size 5" 5.25"
    Woofer Composition Aluminum
    Woofer Surround Material n/a Rubber
    Tweeter Size 0.875" 1"
    Tweeter Type Dome Hard-Dome
    Aimable Tweeter No No
    Midrange Driver No No
    Firing Direction rear rear
    Physical Specs
    Height 710.0mm (28") 277.8mm (10.9")
    Width 250.0mm (9.8") 200.0mm (7.9")
    Depth 296.0mm (11.7") 322.3mm (12.7")
    Weight 11.80kg (26lbs) 10.00kg (22lbs)
    Enclosure Bass Reflex Bass Reflex
    Available Colors Black, White, Walnut n/a
    Mounting Bracket No No
    Grille Yes n/a
    Moisture Resistancy No No
    Connections
    Aux Inputs 3.5mm, Stereo RCA 3.5mm
    USB Port USB-B Service only
    Phone Input No No
    Subwoofer Output mono-RCA Wired
    Digital Input Optical Optical, Coax
    HDMI Input No eARC
    Headphone Jack No No
    Ethernet Port n/a Yes
    Other
    Parts Warranty 2 Years 1 Year
    Labor Warranty 2 Years 1 Year

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