In this review, we will be comparing XT20 and Q350, two Passive Bookshelf speakers from Polk Audio and KEF.
Let's have a brief look at the main features
of Polk XT20 and KEF Q350 first before getting into our more
detailed comparison.
| Key Specs | Polk XT20 | KEF Q350 |
|---|
| 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" Soft-Dome | 1" Dome |
|---|
| Woofer | 6.5" Bi-laminate paper | 6.5" Aluminum |
|---|
| Frequency response | 38-40k Hz | 63-28k Hz |
|---|
| Sensitivity | 87 dB | 87 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 30-200 watts | 10-120 watts |
|---|
| Weight | 5.45kg / 12lbs | 7.60kg / 16.7lbs |
|---|
| Dimensions (H x W x D) | 13-1/16" x 7-9/16" x 11-1/16"
332.0 x 193.0 x 281.0mm | 14.0" x 8.2" x 12.0"
358.0 x 210.0 x 306.0mm |
|---|
What size room are the Polk XT20 and KEF Q350 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 XT20 |
KEF Q350 |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Average |
| Very Large Room |
Poor |
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 XT20 and Q350 are 2-way speakers.
Polk XT20KEF Q350
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 XT20 |
KEF Q350 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 6.5-inch
|
1 x 6.5-inch
|
XT20 features a 1" Soft-Dome Tweeter and 1 x 6.5" Bi-laminate paper Woofer. On the other hand, the Q350 features a 1" vented aluminum Dome Tweeter and 1 x 6.5" Aluminum Woofer with a Crossover frequency at 2500Hz.
Frequency Response
XT20 has a frequency range of 38-40k Hz whereas Q350 has a frequency range of 63-28k Hz. With a minimum frequency of 38Hz, the XT20 can go significantly deeper on the low side and provide stronger bass compared to the Q350's min frequency of 63Hz.
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
XT20 and Q350 have the same Impedance of 8 ohms and their sensitivity is also same at 87 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.
XT20 can handle a max power of 200 watts RMS, whereas Q350 has a max power handling value of 120 watts RMS, 80 watts less than the XT20.
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
XT20 features Post type posts and Q350 has a Post type posts. None of these speakers feature bi-amping/bi-wiring.
KEF Q350's Post terminals
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 XT20's and KEF Q350's external dimensions. Polk XT20 has external dimensions of 332.0 x 193.0 x 281.0mm (13-1/16 x 7-9/16 x 11-1/16inch) whereas KEF Q350 has external dimensions of 358.0 x 210.0 x 306.0mm (14.0 x 8.2 x 12.0inch).
KEF Q350 is clearly the larger of the two speakers. Its body is 17mm wider, 26mm taller and 25mm deeper than Polk XT20.
Below you can see the front view size comparison of Polk XT20 and KEF Q350 in scale.
Comparison image of Polk XT20 and KEF Q350 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 XT20 is approximately 542.3cm2 / 84.1inch2 and base area of the KEF Q350 is approximately 642.6cm2 / 99.6inch2. The XT20 requires 16% less surface area than the Q350 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 XT20 and KEF Q350 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 XT20 weighs 5.45kg / 12lbs and the KEF Q350 weighs 7.60kg / 16.7lbs. This makes the Q350 39% heavier than the XT20.
Here is a comparison of how XT20 and Q350'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 XT20?
Here are the items that are included inside the box of XT20:
- 2 Bookshelf loudspeakers
- 2 Grilles (attached)
- 8 Self-adhesive rubber feet
- Owners Manual
- Online Product Registration
What's in the Box of KEF Q350?
Here are the items that come with the Q350:
- 2 Bookshelf loudspeakers
- 2 Foam port plugs
- 8 Self-adhesive rubber feet
- Owner's Manual
- Warranty Registration Card
 Max Input Power |
200 watts
vs
120 watts
|
Handle more power from your amplifier |
 Low Frequency Response |
38 Hz
vs
63 Hz
|
Generates deeper bass |
 High Frequency Response |
40k Hz
vs
28k Hz
|
Generates higher frequency |
 Height |
332mm
vs
358mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
542cm2
vs
642cm2
|
Takes less floor space |
 Price per pair* |
299USD
vs
750USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Polk Audio Monitor XT20 |
KEF Q350 |
| Brand |
Polk Audio |
KEF |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
30-200 watts |
10-120 watts |
| Sensitivity |
87 dB |
87 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
n/a |
3.7 ohms |
| Frequency Response |
38-40k Hz |
63-28k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
Bi-laminate paper |
Aluminum |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Soft-Dome |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
2500Hz |
| Firing Direction |
n/a |
rear |
Physical Specs |
|
|
| Height |
332.0mm (13.1") |
358.0mm (14.1") |
| Width |
193.0mm (7.6") |
210.0mm (8.3") |
| Depth |
281.0mm (11.1") |
306.0mm (12") |
| Weight |
5.45kg (12lbs) |
7.60kg (16.7lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF, Vinyl |
MDF/Vinyl-wrapped |
| Available Colors |
Black |
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 |
These sit in different price classes - KEF Q350 costs roughly 2.5x what Polk XT20 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 | Polk XT20 digs deeper - 38Hz against 63Hz. |
| Amplifier needs | evenly matched | Similar sensitivity (87dB vs 87dB) - both want much the same power. |
| Headroom | A | Polk XT20 takes more power (200W vs 120W) - more in hand in a big room. |
| Size | depends | Polk XT20 is easier to place; KEF Q350 is bigger, which usually goes with fuller bass. Your room decides. |
| Price | A | Polk XT20 is cheaper - $299 against $750, about 60% less; arguably a different class. |
A Polk XT20 B KEF Q350
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?
Polk XT20 is the easier recommendation: it leads on most of the measured areas and costs less. Take KEF Q350 if its size, looks or fit in your room suit you better. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 63Hz anyway, so judge these on the other rows instead. Think about the whole system, not just the speakers: the roughly $451 saved by taking the cheaper pair would buy a subwoofer or a better amplifier, and either usually does more for the sound than the difference between these two.
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.