In this review, we will be comparing C 91 II and Q150, two Passive Bookshelf speakers from Jamo and KEF.
Let's have a brief look at the main features
of Jamo C 91 II and KEF Q150 first before getting into our more
detailed comparison.
| Key Specs | Jamo C 91 II | KEF Q150 |
|---|
| Brand | Jamo
Denmark · founded 1966 | KEF
United Kingdom · founded 1961 |
|---|
| Design | 2-way | 2-way |
|---|
| Uni-Q driver | — | 11th Generation Uni-Q |
|---|
| Tweeter | 1" Soft-Dome | 1" Dome |
|---|
| Woofer | 4" Composite | 5.25" Aluminum |
|---|
| Frequency response | 65-24k Hz | 51-28k Hz |
|---|
| Sensitivity | 86 dB | 86 dB |
|---|
| Impedance | 6 ohms | 8 ohms |
|---|
| Power range | 50-100 watts | 10-100 watts |
|---|
| Weight | 4.10kg / 9lbs | 5.60kg / 12.3lbs |
|---|
| Dimensions (H x W x D) | 10.4" x 6.7" x 7.5"
265.0 x 171.0 x 191.0mm | 11.9" x 7.0" x 10.9"
303.0 x 180.0 x 278.0mm |
|---|
What size room are the Jamo C 91 II 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* |
Jamo C 91 II |
KEF Q150 |
| Near-field |
Average |
Average |
| Small Room |
Good |
Good |
| Mid-size Room |
Average |
Average |
| Large Room |
Poor |
Poor |
| Very Large Room |
Bad |
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.
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through our links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both C 91 II and Q150 are 2-way speakers.
Jamo C 91 IIKEF 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 |
Jamo C 91 II |
KEF Q150 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 4-inch
|
1 x 5.25-inch
|
C 91 II features a 1" Soft-Dome Tweeter and 1 x 4" Composite Woofer. 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
C 91 II has a frequency range of 65-24k 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 C 91 II's min frequency of 65Hz.
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
C 91 II is a 6 ohms speaker compared to the Q150 which has a nominal impedance of 8 ohms.
On the other hand, they have the same sensitivity of 86 dBdB.
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.
Both handle the same maximum of 100 watts RMS, though C 91 II is rated 50-100 watts and Q150 10-100 watts.
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
C 91 II features Post type posts and Q150 has a Post type posts. None of these speakers feature bi-amping/bi-wiring.
Jamo C 91 II's 5-way post terminals
KEF Q150's Post terminals
Cabinet Type and Port Position
Both C 91 II 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.
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 Jamo C 91 II's and KEF Q150's external dimensions. Jamo C 91 II has external dimensions of 265.0 x 171.0 x 191.0mm (10.4 x 6.7 x 7.5inch) whereas KEF Q150 has external dimensions of 303.0 x 180.0 x 278.0mm (11.9 x 7.0 x 10.9inch).
KEF Q150 is clearly the larger of the two speakers. Its body is 9mm wider, 38mm taller and 87mm deeper than Jamo C 91 II.
Below you can see the front view size comparison of Jamo C 91 II and KEF Q150 in scale.
Comparison image of Jamo C 91 II 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 Jamo C 91 II is approximately 326.6cm2 / 50.6inch2 and base area of the KEF Q150 is approximately 500.4cm2 / 77.6inch2. The C 91 II requires 35% 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 Jamo C 91 II 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 Jamo C 91 II weighs 4.10kg / 9lbs and the KEF Q150 weighs 5.60kg / 12.3lbs. This makes the Q150 37% heavier than the C 91 II.
Here is a comparison of how C 91 II 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 Jamo C 91 II?
Here are the items that are included inside the box of C 91 II:
- 2 Bookshelf loudspeakers
- 2 Grilles
- 8 Self-adhesive rubber feet
- 4 Self-adhesive rubber bumpers
- User Manual
- Important Safety Instructions Warranty Information
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
 Mounting Bracket |
Yes
vs
No
|
Allows mounting on walls |
 Height |
265mm
vs
303mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
326cm2
vs
500cm2
|
Takes less floor space |
 Price per pair* |
459USD
vs
600USD
|
costs less (*prices may change depending on the seller, location and time) |
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Woofer Size |
5.25 inches
vs
4 inches
|
Larger woofer |
|
Low Frequency Response |
51 Hz
vs
65 Hz
|
Generates deeper bass |
 High Frequency Response |
28k Hz
vs
24k Hz
|
Generates higher frequency |
| General |
Jamo Concert 9 Series C 91 II |
KEF Q150 |
| Brand |
Jamo |
KEF |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
50-100 watts |
10-100 watts |
| Sensitivity |
86 dB |
86 dB |
| Impedance |
6 ohms |
8 ohms |
| Impedance |
n/a |
3.7 ohms |
| Frequency Response |
65-24k Hz |
51-28k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
4" |
5.25" |
| Woofer Composition |
Composite |
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 |
rear |
rear |
Physical Specs |
|
|
| Height |
265.0mm (10.4") |
303.0mm (11.9") |
| Width |
171.0mm (6.7") |
180.0mm (7.1") |
| Depth |
191.0mm (7.5") |
278.0mm (10.9") |
| Weight |
4.10kg (9lbs) |
5.60kg (12.3lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Wood-grain |
MDF/Vinyl-wrapped |
| Available Colors |
White Oak,Black Ash |
Black, Walnut, White |
| Mounting Bracket |
Keyhole |
No |
| Recommended Stand Height |
28-32" |
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 65Hz. |
| Amplifier needs | evenly matched | Similar sensitivity (86dB vs 86dB) - both want much the same power. |
| Amplifier match | B | KEF Q150 is the easier load at 8 ohms. |
| Headroom | evenly matched | Similar power handling (100W vs 100W). |
| Size | depends | Jamo C 91 II is easier to place; KEF Q150 is bigger, which usually goes with fuller bass. Your room decides. |
| Price | A | Jamo C 91 II is cheaper - $459 against $600, about 24% less. |
A Jamo C 91 II 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?
The usual trade-off: KEF Q150 measures better, Jamo C 91 II costs about about 31% more% less. Whether that gap is worth the money is the call only you can make - and in a normal room it is often smaller than the numbers suggest. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 65Hz anyway, which makes the cheaper Jamo C 91 II much easier to justify. In a large or open-plan room, KEF Q150 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Jamo C 91 II 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.