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Emotiva Airmotiv B2+ vs KEF Q150 Comparison

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Emotiva Airmotiv B2+

Passive Bookshelf | 40-28k Hz

Emotiva Airmotiv B2+
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KEF Q150

Passive Bookshelf | 51-28k Hz

KEF Q150
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Emotiva Airmotiv B2+ Emotiva Airmotiv B2+
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KEF Q150 KEF Q150
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Emotiva Airmotiv B2+
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KEF Q150
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Emotiva Airmotiv B2+ vs KEF Q150 Speaker Comparison

In this review, we will be comparing Airmotiv B2+ and Q150, two Passive Bookshelf speakers from Emotiva and KEF.

Let's have a brief look at the main features of Emotiva Airmotiv B2+ and KEF Q150 first before getting into our more detailed comparison.

Emotiva Airmotiv B2+ Key Specs

  • 2-way Design
  • 25×32 mm" folded ribbon Tweeter
  • 6.25" woven fiber cone Woofer
  • 40-28k Hz Frequency Response
  • 86 dB Sensitivity
  • Impedance: 4ohms
  • Power Range:Up to 125watts
  • Weight:7.10kg
  • Dimensions (H x W x D): 324.0" x 8-1/2" x 11-1/2"( 324.0 x 216.0 x 293.0mm )

KEF Q150 Key Specs

  • 2-way Design
  • 11th Generation Uni-Q Driver
  • 1" Dome Tweeter
  • 5.25" Aluminum Woofer
  • 51-28k Hz Frequency Response
  • 86 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:10-100watts
  • Weight:5.60kg
  • Dimensions (H x W x D): 303.0" x 7.0" x 10.9"( 303.0 x 180.0 x 278.0mm )

What size room are the Emotiva Airmotiv B2+ and KEF Q150 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* Emotiva Airmotiv B2+ KEF Q150
Near-field Average Average
Small Room Good Good
Mid-size Room Average Average
Large Room Poor Poor
Very Large Room Bad 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 Emotiva Airmotiv B2+ and KEF Q150 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 Airmotiv B2+ and Q150 are 2-way speakers.

Driver Emotiva Airmotiv B2+ KEF Q150
Driver Setup 2-way 2-way
Tweeter 25×32 mm-inch 1-inch
Midrange - -
Woofer 1 x 6.25-inch 1 x 5.25-inch

Airmotiv B2+ features a 25×32 mm" folded ribbon Tweeter and 1 x 6.25" woven fiber cone Woofer with a Crossover frequency at 2000Hz. On the other hand, the Q150 features a 1" vented aluminum Dome Tweeter and 1 x 5.25" Aluminum Woofer with a Crossover frequency at 2500Hz.

Frequency Response

Airmotiv B2+ has a frequency range of 40-28k Hz whereas Q150 has a frequency range of 51-28k Hz. With a minimum frequency of 40Hz, the Airmotiv B2+ can go significantly deeper on the low side and provide stronger bass compared to the Q150's min frequency of 51Hz.

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 Bookshelf class in our database.

Low Frequency

Bookshelf Speakers

Airmotiv B2+
Q150
Min
Average
Max
High Frequency

Bookshelf Speakers

Emotiva Airmotiv B2+
KEF Q150
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

Airmotiv B2+ is a 4 ohms speaker compared to the Q150 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 Airmotiv B2+ can provide this impedance level.

On the other hand, they have the same sensitivity of 86 dBdB.

Sensitivity

Bookshelf Speakers

Airmotiv B2+
Q150
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.

Airmotiv B2+ can handle a max power of 125 watts RMS from the amp the whereas Q150 has a max power handling value of 100 watts RMS, 25 watts less than the Airmotiv B2+.

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

Airmotiv B2+ features Binding post posts which make bi-amping or bi-wiring possible. Q150 has a Post which doesn't feature bi-amping/bi-wiring.

Emotiva Airmotiv B2+ Terminals
Emotiva Airmotiv B2+'s Binding post terminals allows Bi-amping or bi-wiring

KEF Q150 Terminals
KEF Q150's Post terminals

Cabinet Type and Port Position

Both Airmotiv B2+ and Q150 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.

Emotiva Airmotiv B2+  Port
Emotiva Airmotiv B2+ Port

KEF Q150  Port
KEF Q150 Port

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 Emotiva Airmotiv B2+'s and KEF Q150's external dimensions. Emotiva Airmotiv B2+ has external dimensions of 324.0 x 216.0 x 293.0mm ( 12-3/4-inch x 8-1/2-inch x 11-1/2-inch) whereas KEF Q150 has external dimensions of 303.0 x 180.0 x 278.0mm ( 11.9 x 7.0 x 10.9inch) .

Emotiva Airmotiv B2+ is clearly the larger of the two speakers. Its body is 36mm wider, 21mm taller and 15mm deeper than KEF Q150.

Below you can see the front view size comparison of Emotiva Airmotiv B2+ and KEF Q150 in scale.

Emotiva Airmotiv B2+ vs KEF Q150 Size Comparison - Front View
Comparison image of Emotiva Airmotiv B2+ and KEF Q150 Size and External Dimensions

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 Emotiva Airmotiv B2+ is approximately 632.9cm2 / 98.1inch2 and base area of the KEF Q150 is approximately 500.4cm2 / 77.6inch2. The Airmotiv B2+ requires 26% more surface area than the Q150 which gives it a small disadvantage on placement in tight spaces.

Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:

Emotiva Airmotiv B2+ vs KEF Q150 Size Comparison on a Media Console
Size Comparison image of Emotiva Airmotiv B2+ and KEF Q150 on a Media Console
Weight Comparison

The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Emotiva Airmotiv B2+ weighs 7.10kg / 15.6lbs and the KEF Q150 weighs 5.60kg / 12.3lbs. This makes the Airmotiv B2+ 27% heavier than the Q150.

Here is a comparison of how Airmotiv B2+ and Q150's weights compare with the average, max and min weights in Passive Bookshelf class.

Weight
All Bookshelf Speakers
Emotiva Airmotiv B2+
KEF Q150
Min
Average
Max

What's in the Box of KEF Q150?

Here are the items that come with the Q150:
  • 2 Bookshelf loudspeakers
  • 2 Foam port plugs
  • 8 Self-adhesive rubber feet
  • Owner's Manual
  • Warranty Registration Card

  • Reasons to choose Emotiva Airmotiv B2+ over KEF Q150
    Max Input Power 125 watts vs 100 watts Handle more power from your amplifier
    Woofer Size 6.25 inches vs 5.25 inches Larger woofer
    Low Frequency Response 40 Hz vs 51 Hz Generates deeper bass
    Bi-Amping and Bi-Wiring Yes vs No Allows bi-amping and bi-wiring connections
    Price per pair* 499USD vs 600USD costs less (*prices may change depending on the seller, location and time)

    Reasons to choose KEF Q150 over Emotiva Airmotiv B2+

    Nominal Impedance 8 ohms vs 4 ohms Less selective with amplifiers
    Height 303mm vs 324mm Easier to fit in smaller spaces
    Base Surface Area 500cm2 vs 632cm2 Takes less floor space
    Emotiva Airmotiv B2+ vs KEF Q150 Specs Table
    Detailed comparison of specifications
    General Emotiva Airmotiv B2+ KEF Q150
    Brand Emotiva KEF
    Speaker Type Bookshelf speakers Bookshelf speakers
    Power Range Up to 125 watts 10-100 watts
    Sensitivity 86 dB 86 dB
    Impedance 4 ohms 8 ohms
    Impedance n/a 3.7 ohms
    Frequency Response 40-28k Hz 51-28k Hz
    Drivers
    Woofer Quantity 1 1
    Woofer Size 6.25" 5.25"
    Woofer Composition woven fiber cone Aluminum
    Woofer Surround Material SBR Rubber
    Tweeter Size 25×32 mm" 1"
    Tweeter Type folded ribbon Dome
    Aimable Tweeter No No
    Midrange Driver No No
    Crossover Frequency 2000Hz 2500Hz
    Firing Direction rear rear
    Physical Specs
    Height 324.0mm (12.8") 303.0mm (11.9")
    Width 216.0mm (8.5") 180.0mm (7.1")
    Depth 293.0mm (11.5") 278.0mm (10.9")
    Weight 7.10kg (15.6lbs) 5.60kg (12.3lbs)
    Enclosure Bass reflex Bass Reflex
    Finish HDF MDF/Vinyl-wrapped
    Available Colors Black Black, Walnut, White
    Mounting Bracket No No
    Recommended Stand Height n/a 18-24"
    Grille Yes Yes
    Moisture Resistancy No No
    Connections
    Biamp Inputs Yes No
    Other
    Parts Warranty 5 Years 5 Years
    Labor Warranty 5 Years 5 Years

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