In this review, we will be comparing two different types of speakers by KEF. KEF Q550 is a Floor-standing speaker whereas the LS50 is a Bookshelf speaker.
Let's have a brief look at the main features
of KEF Q550 and KEF LS50 first before getting into our more
detailed comparison.
| Key Specs | KEF Q550 | KEF LS50 |
|---|
| Brand | KEF United Kingdom · founded 1961 | KEF United Kingdom · founded 1961 |
|---|
| Design | 2-way | 2-way |
|---|
| Uni-Q driver | 11th Generation Uni-Q | 11th Generation Uni-Q |
|---|
| Tweeter | 1" Dome | 1" Vented dome |
|---|
| Woofer | 2 x 5.25" Aluminum | 5.25" Magnesium/aluminum alloy |
|---|
| Frequency response | 58-28k Hz | 79-28k Hz |
|---|
| Sensitivity | 87 dB | 85 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 15-130 watts | 25-100 watts |
|---|
| Weight | 14.55kg / 32lbs | 7.20kg / 15.8lbs |
|---|
| Dimensions (H x W x D) | 35-3/16" x 11-5/8" x 12-5/16" 894.0 x 296.0 x 313.0mm | 11.8" x 7.8" x 10.9" 302.0 x 200.0 x 278.0mm |
|---|
What size room are the KEF Q550 and KEF LS50 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 Q550 |
KEF LS50 |
| Near-field |
Bad |
Average |
| Small Room |
Poor |
Good |
| Mid-size Room |
Good |
Average |
| Large Room |
Good |
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 Q550 and LS50 are 2-way speakers.
KEF Q550KEF LS50
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 Q550 |
KEF LS50 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5.25-inch
|
1 x 5.25-inch
|
Q550 features a 1" vented aluminum Dome Tweeter and 2 x 5.25" Aluminum Woofer with a Crossover frequency at 2500Hz. On the other hand, the LS50 features a 1" Aluminum Vented dome Tweeter and 1 x 5.25" Magnesium/aluminum alloy Woofer with a Crossover frequency at 2200Hz.
Frequency Response
Q550 has a frequency range of 58-28k Hz whereas LS50 has a frequency range of 79-28k Hz. With a minimum frequency of 58Hz, the Q550 can go significantly deeper on the low side and provide stronger bass compared to the LS50's min frequency of 79Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing 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
Q550 and LS50 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Q550 sensitivity is rated at 87 dB and the LS50's is at 85 dB. This 2 dB difference makes the KEF Q550 a more sensitive speaker compared to KEF LS50, hence will play louder with the same amount of watts.
Sensitivity
Floor-standing 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.
Q550 can handle a max power of 130 watts RMS, whereas LS50 has a max power handling value of 100 watts RMS, 30 watts less than the Q550.
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
Q550 features Post type posts and LS50 has a Post type posts. None of these speakers feature bi-amping/bi-wiring.
KEF LS50's Post terminals
Cabinet Type and Port Position
Q550 has a front firing port whereas LS50 has a rear firing ports. KEF Q550's front-firing port gives more flexibility in placement in regards to proximity to walls compared to KEF LS50 with its rear-firing 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 Q550's and KEF LS50's external dimensions. KEF Q550 has external dimensions of 894.0 x 296.0 x 313.0mm (35-3/16 x 11-5/8 x 12-5/16inch) whereas KEF LS50 has external dimensions of 302.0 x 200.0 x 278.0mm (11.8 x 7.8 x 10.9inch).
KEF Q550 is clearly the larger of the two speakers. Its body is 96mm wider, 592mm taller and 35mm deeper than KEF LS50.
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 Q550 is approximately 926.5cm2 / 143.6inch2 and base area of the KEF LS50 is approximately 556.0cm2 / 86.2inch2. The Q550 requires 67% more surface area than the LS50 which gives it a small disadvantage on placement in tight spaces.
What's in the Box of KEF Q550?
Here are the items that are included inside the box of Q550:
- Floorstanding loudspeaker
- 2 Outrigger feet
- 4 Spikes
- 6 Screws
- 6 Washers
- 4 Rubber inserts
- Hex-key
- Owners Manual
- Warranty Information
What's in the Box of KEF LS50?
Here are the items that come with the LS50:
- 2 Bookshelf loudspeakers
- 2 Foam port plugs
- 8 Self-adhesive rubber feet
- Owner's Manual
- Warranty Registration Card