In this review, we will be comparing Q750 and BW 603, two Passive Floor-standing speakers from KEF and Bowers Wilkins.
Let's have a brief look at the main features
of KEF Q750 and B&W 603 first before getting into our more
detailed comparison.
| Key Specs | KEF Q750 | B&W 603 |
|---|
| Brand | KEF
United Kingdom · founded 1961 | Bowers Wilkins
United Kingdom · founded 1966 |
|---|
| Design | 2-way | 3-way |
|---|
| Uni-Q driver | 11th Generation Uni-Q | — |
|---|
| Tweeter | 1" Dome | 1" |
|---|
| Midrange | — | 6" |
|---|
| Woofer | 2 x 6.5" Aluminum | 2 x 6.5" Paper |
|---|
| Frequency response | 48-28k Hz | 48-28k Hz |
|---|
| Sensitivity | 88 dB | 88.5 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 15-150 watts | 30-200 watts |
|---|
| Weight | 16.59kg / 36.5lbs | 24.14kg / 53.1lbs |
|---|
| Dimensions (H x W x D) | 37-3/16" x 12-7/8" x 12-3/8"
945.0 x 328.0 x 315.0mm | 38.7" x 7.4" x 13.3"
985.0 x 190.0 x 340.0mm |
|---|
What size room are the KEF Q750 and B&W 603 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 Q750 |
B&W 603 |
| Near-field |
Bad |
Bad |
| Small Room |
Poor |
Poor |
| Mid-size Room |
Good |
Good |
| Large Room |
Good |
Good |
| 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
One of the fundamental differences between these two speakers is that Q750 is a 2-way design whereas the BW 603 is a 3-way speaker. 3-way designs utilize a midrange driver in addition to the tweeter and woofer on 2-way designs. Designing a crossover for a 3-way speaker is a complicated process and generally increases the overall cost of the speaker.
KEF Q750B&W 603
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
KEF Q750 |
B&W 603 |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
1 x 6-inch |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
Q750 features a 1" vented aluminum Dome Tweeter and 2 x 6.5" Aluminum Woofer with a Crossover frequency at 2500Hz. On the other hand, the BW 603 features a 1" Tweeter, a 6" Midrange and 2 x 6.5" Paper Woofer.
Frequency Response
Q750 and BW 603 has exactly the same frequency range of 48-28k Hz.
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
Q750 and BW 603 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Q750 sensitivity is rated at 88 dB and the BW 603's is at 88.5 dB. This 1 dB difference makes the B&W 603 a more sensitive speaker compared to KEF Q750, 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.
BW 603 can handle a max power of 200 watts RMS, whereas Q750 has a max power handling value of 150 watts RMS, 50 watts less than the BW 603.
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
BW 603 features Post posts which make bi-amping or bi-wiring possible. Q750 has a Binding post which doesn't feature bi-amping/bi-wiring.
KEF Q750's Binding post terminals
Cabinet Type and Port Position
Q750 has a front firing port whereas BW 603 has a rear firing ports. KEF Q750's front-firing port gives more flexibility in placement in regards to proximity to walls compared to B&W 603 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 Q750's and B&W 603's external dimensions. KEF Q750 has external dimensions of 945.0 x 328.0 x 315.0mm (37-3/16 x 12-7/8 x 12-3/8inch) whereas B&W 603 has external dimensions of 985.0 x 190.0 x 340.0mm (38.7 x 7.4 x 13.3inch).
KEF Q750 is 40mm shorter and 25mm less deeper than B&W 603 but it is also 138mm wider.
Below you can see the front view size comparison of KEF Q750 and B&W 603 in scale.
Comparison image of KEF Q750 and B&W 603 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 Q750 is approximately 1033.2cm2 / 160.1inch2 and base area of the B&W 603 is approximately 646.0cm2 / 100.1inch2. The Q750 requires 60% more surface area than the BW 603 which gives it a small disadvantage on placement in tight spaces.
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 Q750 weighs 16.59kg / 36.5lbs and the B&W 603 weighs 24.14kg / 53.1lbs. This makes the BW 603 46% heavier than the Q750.
Here is a comparison of how Q750 and BW 603's weights compare with the average, max and min weights in Passive Floor-standing class.
Weight
All Floor-standing Speakers
What's in the Box of KEF Q750?
Here are the items that are included inside the box of Q750:
- 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 B&W 603?
Here are the items that come with the BW 603:
- Floorstanding loudspeaker
- Grille
- Plinith (base)
- 2 Jumper-straps (pre-installed)
- 4 Rubber feet
- 4 Spike feet
- 4 Hex-nuts
- 4 Screws
- 4 Washers
- 4 Lock-washers
- Two-piece foam port plug
- Hex-key
- Manual
- Bowers & Wilkins brochure
- Warranty Information
 Port Position |
Front
vs
Rear
|
Gives more flexibility placing close to walls |
 Passive Radiator |
2 x 6.25-inch
vs
None
|
Increases the bass performance |
 Dolby Atmos Drivers |
Optional
vs
No
|
Dolby Atmos Compatibility |
 Height |
945mm
vs
985mm
|
Easier to fit in smaller spaces |
 Max Input Power |
200 watts
vs
150 watts
|
Handle more power from your amplifier |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 Sensitivity |
89 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Bi-Amping and Bi-Wiring |
Yes
vs
No
|
Allows bi-amping and bi-wiring connections |
 Base Surface Area |
646cm2
vs
1033cm2
|
Takes less floor space |
| General |
KEF Q750 |
Bowers & Wilkins 603 |
| Brand |
KEF |
Bowers Wilkins |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
15-150 watts |
30-200 watts |
| Sensitivity |
88 dB |
88.5 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
3.8 ohms |
n/a |
| Frequency Response |
48-28k Hz |
48-28k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
Aluminum |
Paper |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Dome |
n/a |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
6" |
| Crossover Frequency |
2500Hz |
n/a |
| Firing Direction |
front |
rear |
Physical Specs |
|
|
| Height |
945.0mm (37.2") |
985.0mm (38.8") |
| Width |
328.0mm (12.9") |
190.0mm (7.5") |
| Depth |
315.0mm (12.4") |
340.0mm (13.4") |
| Weight |
16.59kg (36.5lbs) |
24.14kg (53.1lbs) |
| Enclosure |
Passive Radiator |
Bass Reflex |
| Finish |
MDF/Wood-grain vinyl |
MDF/Vinyl |
| Available Colors |
Walnut |
Black, White, Oak |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
Yes |
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 | evenly matched | Much the same reach (48Hz vs 48Hz). |
| Amplifier needs | evenly matched | Similar sensitivity (88dB vs 89dB) - both want much the same power. |
| Headroom | B | B&W 603 takes more power (200W vs 150W) - more in hand in a big room. |
| Size | depends | B&W 603 is easier to place; KEF Q750 is bigger, which usually goes with fuller bass. Your room decides. |
| Cabinet | depends | Passive Radiator vs Ported. |
| Expandability | depends | KEF Q750: Atmos drivers; B&W 603: bi-amping. KEF Q750 sits in a wider range (7 models), so a matched surround system is easier later. |
A KEF Q750 B B&W 603
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?
B&W 603 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. In a large or open-plan room, KEF Q750 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, B&W 603 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.