In this review, we will be comparing Q150 and L100, two Passive Bookshelf speakers from KEF and Polk Audio.
Let's have a brief look at the main features
of KEF Q150 and Polk L100 first before getting into our more
detailed comparison.
| Key Specs | KEF Q150 | Polk L100 |
|---|
| Brand | KEF
United Kingdom · founded 1961 | Polk Audio
United States · founded 1972 |
|---|
| Design | 2-way | 2-way |
|---|
| Uni-Q driver | 11th Generation Uni-Q | — |
|---|
| Tweeter | 1" Dome | 1" Ring Radiator |
|---|
| Woofer | 5.25" Aluminum | 5.25" Polypropylene |
|---|
| Frequency response | 51-28k Hz | 57-38k Hz |
|---|
| Sensitivity | 86 dB | 85.5 dB |
|---|
| Impedance | 8 ohms | 4 ohms |
|---|
| Power range | 10-100 watts | 30-160 watts |
|---|
| Weight | 5.60kg / 12.3lbs | 7.68kg / 16.9lbs |
|---|
| Dimensions (H x W x D) | 11.9" x 7.0" x 10.9"
303.0 x 180.0 x 278.0mm | 13-11/16" x 7-7/8" x 11-5/16"
348.0 x 201.0 x 288.0mm |
|---|
What size room are the KEF Q150 and Polk L100 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 L100 |
| 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.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both Q150 and L100 are 2-way speakers.
KEF Q150Polk L100
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
KEF Q150 |
Polk L100 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 5.25-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 L100 features a 1" Ring Radiator Tweeter and 1 x 5.25" Polypropylene Woofer with a Crossover frequency at 2900Hz.
Frequency Response
Q150 has a frequency range of 51-28k Hz whereas L100 has a frequency range of 57-38k Hz. With a minimum frequency of 51Hz, the Q150 can go significantly deeper on the low side and provide stronger bass compared to the L100's min frequency of 57Hz.
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
Q150 is a 8 ohms speaker compared to the L100 which has a nominal impedance of 4 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 L100 can provide this impedance level.
These two speakers also have different sensitivity levels. Q150 sensitivity is rated at 86 dB and the L100's is rated at 85.5 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.
L100 can handle a max power of 160 watts RMS, whereas Q150 has a max power handling value of 100 watts RMS, 60 watts less than the L100.
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
Q150 features Post type posts and L100 has a Post type posts. None of these speakers feature bi-amping/bi-wiring.
KEF Q150's Post terminals
Polk L100's Post terminals
Cabinet Type and Port Position
Both Q150 and L100 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
Polk L100 Enhanced Power Port 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 KEF Q150's and Polk L100'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 L100 has external dimensions of 348.0 x 201.0 x 288.0mm (13-11/16 x 7-7/8 x 11-5/16inch).
Polk L100 is clearly the larger of the two speakers. Its body is 21mm wider, 45mm taller and 10mm deeper than KEF Q150.
Below you can see the front view size comparison of KEF Q150 and Polk L100 in scale.
Comparison image of KEF Q150 and Polk L100 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 L100 is approximately 578.9cm2 / 89.7inch2. The Q150 requires 14% less surface area than the L100 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 KEF Q150 and Polk L100 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 KEF Q150 weighs 5.60kg / 12.3lbs and the Polk L100 weighs 7.68kg / 16.9lbs. This makes the L100 37% heavier than the Q150.
Here is a comparison of how Q150 and L100's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of KEF Q150?
Here are the items that are included inside the box of Q150:
- 2 Bookshelf loudspeakers
- 2 Foam port plugs
- 8 Self-adhesive rubber feet
- Owner's Manual
- Warranty Registration Card
What's in the Box of Polk L100?
Here are the items that come with the L100:
- 2 Bookshelf loudspeakers
- 2 Grilles
- Cleaning cloth
- Owners Manual
- Online Registration
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Minimum Impedance |
3.7 ohms
vs
3 ohms
|
Very low impedance levels puts more pressure on amplifier |
 Low Frequency Response |
51 Hz
vs
57 Hz
|
Generates deeper bass |
 Height |
303mm
vs
348mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
500cm2
vs
578cm2
|
Takes less floor space |
 Price per pair* |
600USD
vs
999USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
160 watts
vs
100 watts
|
Handle more power from your amplifier |
 High Frequency Response |
38k Hz
vs
28k Hz
|
Generates higher frequency |
| General |
KEF Q150 |
Polk Audio Legend L100 |
| Brand |
KEF |
Polk Audio |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
10-100 watts |
30-160 watts |
| Sensitivity |
86 dB |
85.5 dB |
| Impedance |
8 ohms |
4 ohms |
| Impedance |
3.7 ohms |
3 ohms |
| Frequency Response |
51-28k Hz |
57-38k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5.25" |
5.25" |
| Woofer Composition |
Aluminum |
Polypropylene |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Dome |
Ring Radiator |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2500Hz |
2900Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
303.0mm (11.9") |
348.0mm (13.7") |
| Width |
180.0mm (7.1") |
201.0mm (7.9") |
| Depth |
278.0mm (10.9") |
288.0mm (11.3") |
| Weight |
5.60kg (12.3lbs) |
7.68kg (16.9lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Vinyl-wrapped |
MDF/Wood veneer |
| Available Colors |
Black, Walnut, White |
Brown Walnut, Black Ash |
| Mounting Bracket |
No |
No |
| Recommended Stand Height |
18-24" |
24-28" |
| 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 |
These sit in different price classes - Polk L100 costs roughly 1.7x what KEF Q150 does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | A | KEF Q150 digs deeper - 51Hz against 57Hz. A subwoofer would even that out. |
| Amplifier needs | evenly matched | Similar sensitivity (86dB vs 86dB) - both want much the same power. |
| Amplifier match | A | KEF Q150 is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | B | Polk L100 takes more power (160W vs 100W) - more in hand in a big room. |
| Size | depends | KEF Q150 is easier to place; Polk L100 is bigger, which usually goes with fuller bass. Your room decides. |
| Price | A | KEF Q150 is cheaper - $600 against $999, about 40% less; arguably a different class. |
A KEF Q150 B Polk L100
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?
KEF Q150 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 57Hz anyway, so judge these on the other rows instead. Match it to your room: we rate KEF Q150 the better fit for near-field listening and a small room, and Polk L100 for a mid-size room and a large 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.