In this review, we will be comparing TSi100 and Q350, two Passive Bookshelf speakers from Polk Audio and KEF.
Let's have a brief look at the main features
of Polk TSi100 and KEF Q350 first before getting into our more
detailed comparison.
| Key Specs | Polk TSi100 | 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" Dome | 1" Dome |
|---|
| Woofer | 5.25" Organic Fiber | 6.5" Aluminum |
|---|
| Frequency response | 61-24k Hz | 63-28k Hz |
|---|
| Sensitivity | 89 dB | 87 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 20-100 watts | 10-120 watts |
|---|
| Weight | 4.53kg / 10lbs | 7.60kg / 16.7lbs |
|---|
| Dimensions (H x W x D) | 11.0" x 7.0" x 10.1"
279.4 x 177.8 x 259.0mm | 14.0" x 8.2" x 12.0"
358.0 x 210.0 x 306.0mm |
|---|
What size room are the Polk TSi100 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 TSi100 |
KEF Q350 |
| 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 TSi100 and Q350 are 2-way speakers.
Polk TSi100KEF 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 TSi100 |
KEF Q350 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 6.5-inch
|
TSi100 features a 1" Dome Tweeter and 1 x 5.25" Organic Fiber Woofer with a Crossover frequency at 2500Hz. 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
TSi100 has a frequency range of 61-24k Hz whereas Q350 has a frequency range of 63-28k Hz. With a minimum frequency of 61Hz, the TSi100 can go slightly deeper then 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
TSi100 and Q350 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. TSi100 sensitivity is rated at 89 dB and the Q350's is at 87 dB. This 2 dB difference makes the Polk TSi100 a more sensitive speaker compared to KEF Q350, 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. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
Q350 can handle a max power of 120 watts RMS, whereas TSi100 has a max power handling value of 100 watts RMS, 20 watts less than the Q350.
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
TSi100 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
Cabinet Type and Port Position
Both TSi100 and Q350 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.
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 TSi100's and KEF Q350's external dimensions. Polk TSi100 has external dimensions of 279.4 x 177.8 x 259.0mm (11.0 x 7.0 x 10.1inch) 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 32.2mm wider, 78.6mm taller and 47mm deeper than Polk TSi100.
Below you can see the front view size comparison of Polk TSi100 and KEF Q350 in scale.
Comparison image of Polk TSi100 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 TSi100 is approximately 460.5cm2 / 71.4inch2 and base area of the KEF Q350 is approximately 642.6cm2 / 99.6inch2. The TSi100 requires 28% 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 TSi100 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 TSi100 weighs 4.53kg / 10lbs and the KEF Q350 weighs 7.60kg / 16.7lbs. This makes the Q350 68% heavier than the TSi100.
Here is a comparison of how TSi100 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 TSi100?
Here are the items that are included inside the box of TSi100:
- 2 Black bookshelf speakers
- Detachable cloth grille (installed)
- 8 Self-adhesive rubber feet
- Owner's Manual
- Wall-Mount template
- Online registration sheet
- Polk Audio product brochure
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
 Sensitivity |
89 dB
vs
87 dB
|
Play louder with same amount of amplification power |
 Low Frequency Response |
61 Hz
vs
63 Hz
|
Generates deeper bass |
 Mounting Bracket |
Yes
vs
No
|
Allows mounting on walls |
 Height |
279mm
vs
358mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
460cm2
vs
642cm2
|
Takes less floor space |
 Price per pair* |
149USD
vs
750USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
120 watts
vs
100 watts
|
Handle more power from your amplifier |
|
Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
 High Frequency Response |
28k Hz
vs
24k Hz
|
Generates higher frequency |
| General |
Polk Audio TSi100 |
KEF Q350 |
| Brand |
Polk Audio |
KEF |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
20-100 watts |
10-120 watts |
| Sensitivity |
89 dB |
87 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
n/a |
3.7 ohms |
| Frequency Response |
61-24k Hz |
63-28k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5.25" |
6.5" |
| Woofer Composition |
Organic Fiber |
Aluminum |
| Woofer Surround Material |
Butyl Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Dome |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2500Hz |
2500Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
279.4mm (11") |
358.0mm (14.1") |
| Width |
177.8mm (7") |
210.0mm (8.3") |
| Depth |
259.0mm (10.2") |
306.0mm (12") |
| Weight |
4.53kg (10lbs) |
7.60kg (16.7lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
Wood-grain vinyl |
MDF/Vinyl-wrapped |
| Available Colors |
Black, Cherry |
Black, Walnut, White |
| Mounting Bracket |
Keyhole |
No |
| Recommended Stand Height |
16-30" |
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 5x what Polk TSi100 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 | evenly matched | Much the same reach (61Hz vs 63Hz). |
| Amplifier needs | A | Polk TSi100 is more sensitive (89dB vs 87dB), so it goes louder on the same amplifier. |
| Headroom | evenly matched | Similar power handling (100W vs 120W). |
| Size | depends | Polk TSi100 is easier to place; KEF Q350 is bigger, which usually goes with fuller bass. Your room decides. |
| Price | A | Polk TSi100 is cheaper - $149 against $750, about 80% less; arguably a different class. |
A Polk TSi100 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 TSi100 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. Match it to your room: we rate Polk TSi100 the better fit for near-field listening and a small room, and KEF Q350 for a mid-size room and a large room. In a large or open-plan room, KEF Q350 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Polk TSi100 is the easier speaker to get right.
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.