In this review, we will be comparing Q150 and RTi A3, two Passive Bookshelf speakers from KEF and Polk Audio.
Let's have a brief look at the main features
of KEF Q150 and Polk RTi A3 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 )
Polk RTi A3 Key Specs
- 2-way Design
- 1" Dome Tweeter
- 6.5" Polymer composite Woofer
- 50-26k Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-150watts
- Weight:7.26kg
- Dimensions (H x W x D): 374.7" x 8.4" x 14.0"( 374.7 x 214.4 x 355.6mm )
What size room are the KEF Q150 and Polk RTi A3 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 |
Polk RTi A3 |
| 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 Polk RTi A3 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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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both Q150 and RTi A3 are 2-way speakers.
| Driver |
KEF Q150 |
Polk RTi A3 |
|
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 RTi A3 features a 1" silk polymer composite Dome Tweeter and 1 x 6.5" Polymer composite Woofer with a Crossover frequency at 2800Hz.
Frequency Response
Q150 has a frequency range of 51-28k Hz whereas RTi A3 has a frequency range of 50-26k Hz. With a minimum frequency of 50Hz, the RTi A3 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 RTi A3 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Q150 sensitivity is rated at 86 dB and the RTi A3's is at 89 dB. This 3 dB difference makes the Polk RTi A3 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 150 watts RMS from the amp the whereas Q150 has a max power handling value of 100 watts RMS , 50 watts less than the RTi A3.
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
RTi A3 features Pair of Dual 5-way Binding Posts - Gold-Plated 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
Q150 has a rear firing port whereas RTi A3 has a back and front firing ports.
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 Polk RTi A3'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 Polk RTi A3 has external dimensions of 374.7 x 214.4 x 355.6mm ( 14.7 x 8.4 x 14.0inch) .
Polk RTi A3 is clearly the larger of the two speakers. Its body is 34.4mm wider, 71.7mm taller and 77.6mm deeper than KEF Q150.
Below you can see the front view size comparison of KEF Q150 and Polk RTi A3 in scale.
Comparison image of KEF Q150 and Polk RTi A3 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 KEF Q150 is approximately 500.4cm2 / 77.6inch2 and base area of the Polk RTi A3 is approximately 762.4cm2 / 118.2inch2. The Q150 requires 34% less surface area than the RTi A3 which gives it a small advantage 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:
Size Comparison image of KEF Q150 and Polk RTi A3 on a Media Console