In this review, we will be comparing CWM7.5 S2 and UIW RLS II, two Passive In-wall speakers from Bowers Wilkins and Definitive Technology.
Let's have a brief look at the main features
of B&W CWM7.5 S2 and Definitive UIW RLS II first before getting into our more
detailed comparison.
| Key Specs | B&W CWM7.5 S2 | Definitive UIW RLS II |
|---|
| Brand | Bowers Wilkins
United Kingdom · founded 1966 | Definitive Technology
United States · founded 1990 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Soft-Dome | 1" Hard-Dome |
|---|
| Woofer | 5" Continuum | 2 x 6.5" Polypropylene |
|---|
| Frequency response | 45-28kHz | 22-30kHz |
|---|
| Sensitivity | 86 dB | 92 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 25-150 watts | 10-350 watts |
|---|
| Weight | 3.81kg / 8.4lbs | — |
|---|
| Dimensions (H x W x D) | 13.0000" x 7.4375" x 4.0625"
331.0 x 189.0 x 104.0mm | 28.5000" x 7.0000" x 3.8750"
724.0 x 178.0 x 99.0mm |
|---|
What size room are the B&W CWM7.5 S2 and Definitive UIW RLS II 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* |
B&W CWM7.5 S2 |
Definitive UIW RLS II |
| Near-field |
Poor |
Are you nuts? |
| Small Room |
Average |
Bad |
| Mid-size Room |
Good |
Poor |
| Large Room |
Average |
Good |
| Very Large Room |
Poor |
Good |
(* 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 CWM7.5 S2 and UIW RLS II are 2-way speakers.
B&W CWM7.5 S2Definitive UIW RLS II
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
B&W CWM7.5 S2 |
Definitive UIW RLS II |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5-inch
|
2 x 6.5-inch
|
CWM7.5 S2 features a 1" Soft-Dome Tweeter and 1 x 5" Continuum Woofer. On the other hand, the UIW RLS II features a 1" Hard-Dome Tweeter and 2 x 6.5" Polypropylene Woofer.
Frequency Response
CWM7.5 S2 has a frequency range of 45-28kHz whereas UIW RLS II has a frequency range of 22-30kHz. With a minimum frequency of 22Hz, the UIW RLS II can go significantly deeper on the low side and provide stronger bass compared to the CWM7.5 S2's min frequency of 45Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the In-wall class in our database.
Low Frequency
In-wall 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
CWM7.5 S2 and UIW RLS II have the same Impedance of 8 ohms but where they differ is the sensitivity levels. CWM7.5 S2 sensitivity is rated at 86 dB and the UIW RLS II's is at 92 dB. This 6 dB difference makes the Definitive UIW RLS II a more sensitive speaker compared to B&W CWM7.5 S2, hence will play louder with the same amount of watts.
Sensitivity
In-wall 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.
UIW RLS II can handle a max power of 350 watts RMS, whereas CWM7.5 S2 has a max power handling value of 150 watts RMS, 200 watts less than the UIW RLS II.
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
CWM7.5 S2 features Spring post type posts and UIW RLS II has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.
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 B&W CWM7.5 S2's and Definitive UIW RLS II's external dimensions. B&W CWM7.5 S2 has external dimensions of 331.0 x 189.0 x 104.0mm (13.0000-inch x 7.4375-inch x 4.0625-inch) whereas Definitive UIW RLS II has external dimensions of 724.0 x 178.0 x 99.0mm (28.5000-inch x 7.0000-inch x 3.8750-inch).
Definitive UIW RLS II is 11mm narrower and 5mm less deeper than B&W CWM7.5 S2 but it is also 393mm taller.
What's in the Box of B&W CWM7.5 S2?
Here are the items that are included inside the box of CWM7.5 S2:
- In-wall loudspeaker
- Mounting frame
- Grille
- Baffle box
- 2 Mounting plates (1 pre-installed)
- Paint shield
- Two-piece foam port plug
- 3 Screws
- 3 Lock-washers
- 2 Wing-nuts
- 2 Fasteners
- Cutout Template
- Installation Instructions
- Warranty Information
What's in the Box of Definitive UIW RLS II?
Here are the items that come with the UIW RLS II:
- In-wall loudspeaker
- Grille
- Self-adhesive foam gasket
- Paint mask
- Wall-Mount Template
- Owners Manual
- Online Product Registration Card