In this review, we will be comparing Q150 and 705 S2, two Passive Bookshelf speakers from KEF and Bowers Wilkins.
Let's have a brief look at the main features
of KEF Q150 and B&W 705 S2 first before getting into our more
detailed comparison.
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 )
B&W 705 S2 Key Specs
- 2-way Design
- 1" Solid Body Soft-Dome Tweeter
- 6.5" Continuum Woofer
- 50-28k Hz Frequency Response
- 88 dB Sensitivity
- Impedance: 8ohms
- Power Range:30-120watts
- Weight:9.32kg
- Dimensions (H x W x D): 407.0" x 7.8" x 11.9"( 407.0 x 200.0 x 301.0mm )
What size room are the KEF Q150 and B&W 705 S2 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* |
KEF Q150 |
B&W 705 S2 |
| Near-field |
Average |
Poor |
| Small Room |
Good |
Average |
| Mid-size Room |
Average |
Good |
| Large Room |
Poor |
Average |
| Very Large Room |
Bad |
Poor |
(* 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 KEF Q150 and B&W 705 S2 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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Drivers
Both Q150 and 705 S2 are 2-way speakers.
| Driver |
KEF Q150 |
B&W 705 S2 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 6.5-inch
|
Q150 features a 1" vented aluminum Dome Tweeter and 1 x 5.25" Aluminum Woofer with a Crossover frequency at 2500Hz. On the other hand, the 705 S2 features a 1" Solid Body Soft-Dome Tweeter and 1 x 6.5" Continuum Woofer .
Frequency Response
Q150 has a frequency range of 51-28k Hz whereas 705 S2 has a frequency range of 50-28k Hz. With a minimum frequency of 50Hz, the 705 S2 can go slightly deeper then 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
High Frequency
Bookshelf Speakers
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
Q150 and 705 S2 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Q150 sensitivity is rated at 86 dB and the 705 S2's is at 88 dB. This 2 dB difference makes the B&W 705 S2 a more sensitive speaker compared to KEF Q150, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf Speakers
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.
Q150 can handle a max power of 120 watts RMS from the amp the whereas Q150 has a max power handling value of 100 watts RMS , 20 watts less than the 705 S2.
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
705 S2 features Binding post posts which make bi-amping or bi-wiring possible. Q150 has a Post which doesn't feature bi-amping/bi-wiring.
KEF Q150's Post terminals
Cabinet Type and Port Position
Both Q150 and 705 S2 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.
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 KEF Q150's and B&W 705 S2's external dimensions. KEF Q150 has external dimensions of 303.0 x 180.0 x 278.0mm ( 11.9 x 7.0 x 10.9inch) whereas B&W 705 S2 has external dimensions of 407.0 x 200.0 x 301.0mm ( 16-inch x 7.8-inch x 11.9-inch) .
B&W 705 S2 is clearly the larger of the two speakers. Its body is 20mm wider, 104mm taller and 23mm deeper than KEF Q150.
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 KEF Q150 is approximately 500.4cm2 / 77.6inch2 and base area of the B&W 705 S2 is approximately 602.0cm2 / 93.3inch2. The Q150 requires 17% less surface area than the 705 S2 which gives it a small advantage on placement in tight spaces.