In this review, we will be comparing R100 and Q150, two Passive Bookshelf speakers from Polk Audio and KEF.
Let's have a brief look at the main features
of Polk R100 and KEF Q150 first before getting into our more
detailed comparison.
| Key Specs | Polk R100 | KEF Q150 |
|---|
| Brand | Polk Audio
United States · founded 1972 | KEF
United Kingdom · founded 1961 |
|---|
| Design | 2-way | 2-way |
|---|
| Uni-Q driver | — | 11th Generation Uni-Q |
|---|
| Tweeter | 1" Pinnacle Ring Radiator | 1" Dome |
|---|
| Woofer | 5.25" Polypropylene Turbine Cone | 5.25" Aluminum |
|---|
| Frequency response | 58-39k Hz | 51-28k Hz |
|---|
| Sensitivity | 86 dB | 86 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 30-150 watts | 10-100 watts |
|---|
| Weight | 5.55kg / 12.2lbs | 5.60kg / 12.3lbs |
|---|
| Dimensions (H x W x D) | 12-13/16" x 6-9/16" x 10-3/16"
326.0 x 167.0 x 259.0mm | 11.9" x 7.0" x 10.9"
303.0 x 180.0 x 278.0mm |
|---|
What size room are the Polk R100 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* |
Polk R100 |
KEF Q150 |
| Near-field |
Poor |
Average |
| Small Room |
Average |
Good |
| Mid-size Room |
Good |
Average |
| Large Room |
Average |
Poor |
| Very Large Room |
Poor |
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.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both R100 and Q150 are 2-way speakers.
Polk R100KEF Q150
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Polk R100 |
KEF Q150 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 5.25-inch
|
R100 features a 1" Pinnacle Ring Radiator Tweeter and 1 x 5.25" Polypropylene Turbine Cone Woofer with a Crossover frequency at 2700Hz. 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
R100 has a frequency range of 58-39k Hz whereas Q150 has a frequency range of 51-28k Hz. With a minimum frequency of 51Hz, the Q150 can go significantly deeper on the low side and provide stronger bass compared to the R100's min frequency of 58Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
R100 and Q150 have the same Impedance of 8 ohms and their sensitivity is also same at 86 dB.
Sensitivity
Bookshelf Speakers
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
R100 can handle a max power of 150 watts RMS, whereas Q150 has a max power handling value of 100 watts RMS, 50 watts less than the R100.
Note that higher power handling does not make a speaker louder: that depends mainly on
sensitivity and impedance. The calculator below shows how loud each of these actually plays
on a real amplifier.
Which plays louder on your amplifier?
Starting with a popular amplifier - change it to the one you own, or any you are
considering, and watch both numbers move.
Input Type and Bi-Amping / Bi-Wiring
R100 features Post type posts and Q150 has a Post type posts. None of these speakers feature bi-amping/bi-wiring.
Polk R100's Binding post terminals
KEF Q150's Post terminals
Cabinet Type and Port Position
Both R100 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.
Polk R100 Port
KEF Q150 Port
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Polk R100's and KEF Q150's external dimensions. Polk R100 has external dimensions of 326.0 x 167.0 x 259.0mm (12-13/16 x 6-9/16 x 10-3/16inch) whereas KEF Q150 has external dimensions of 303.0 x 180.0 x 278.0mm (11.9 x 7.0 x 10.9inch).
Polk R100 is 13mm narrower and 19mm less deeper than KEF Q150 but it is also 23mm taller.
Below you can see the front view size comparison of Polk R100 and KEF Q150 in scale.
Comparison image of Polk R100 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 Polk R100 is approximately 432.5cm2 / 67.0inch2 and base area of the KEF Q150 is approximately 500.4cm2 / 77.6inch2. The R100 requires 14% less surface area than the Q150 which gives it a small advantage on placement in tight spaces.
Here is 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 Polk R100 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 Polk R100 weighs 5.55kg / 12.2lbs and the KEF Q150 weighs 5.60kg / 12.3lbs. This makes the Q150 1% heavier than the R100.
Here is a comparison of how R100 and Q150's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Polk R100?
Here are the items that are included inside the box of R100:
- 2 Bookshelf loudspeakers
- 2 Grilles
- Owners Manual
- Online Registration
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
 Max Input Power |
150 watts
vs
100 watts
|
Handle more power from your amplifier |
 High Frequency Response |
39k Hz
vs
28k Hz
|
Generates higher frequency |
 Base Surface Area |
432cm2
vs
500cm2
|
Takes less floor space |
 Minimum Impedance |
3.7 ohms
vs
3.6 ohms
|
Very low impedance levels puts more pressure on amplifier |
 Low Frequency Response |
51 Hz
vs
58 Hz
|
Generates deeper bass |
 Height |
303mm
vs
326mm
|
Easier to fit in smaller spaces |
 Price per pair* |
600USD
vs
649USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Polk Audio Reserve R100 |
KEF Q150 |
| Brand |
Polk Audio |
KEF |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
30-150 watts |
10-100 watts |
| Sensitivity |
86 dB |
86 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
3.6 ohms |
3.7 ohms |
| Frequency Response |
58-39k Hz |
51-28k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5.25" |
5.25" |
| Woofer Composition |
Polypropylene Turbine Cone |
Aluminum |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Pinnacle Ring Radiator |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2700Hz |
2500Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
326.0mm (12.8") |
303.0mm (11.9") |
| Width |
167.0mm (6.6") |
180.0mm (7.1") |
| Depth |
259.0mm (10.2") |
278.0mm (10.9") |
| Weight |
5.55kg (12.2lbs) |
5.60kg (12.3lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Vinyl |
MDF/Vinyl-wrapped |
| Available Colors |
Black, Walnut, White |
Black, Walnut, White |
| Mounting Bracket |
No |
No |
| Recommended Stand Height |
24-28" |
18-24" |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
No |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
No single best speaker here - they are built to different priorities, and the right one depends on your room, your amplifier and what you listen to.
| Area | Better | Why |
|---|
| Bass | B | KEF Q150 digs deeper - 51Hz against 58Hz. A subwoofer would even that out. |
| Amplifier needs | evenly matched | Similar sensitivity (86dB vs 86dB) - both want much the same power. |
| Headroom | A | Polk R100 takes more power (150W vs 100W) - more in hand in a big room. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Polk R100 sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | evenly matched | Much the same money ($649 vs $600 a pair). |
A Polk R100 B KEF Q150
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Neither runs away with it - they trade advantages. Let the "depends" rows and your own room settle it. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 58Hz anyway, so judge these on the other rows instead. Match it to your room: we rate Polk R100 the better fit for a mid-size room and a large room, and KEF Q150 for near-field listening and a small room.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.