In this review, we will be comparing UIW RLS III and UIW RSS II, two Passive In-wall speakers by Definitive Technology.
Let's have a brief look at the main features
of Definitive UIW RLS III and Definitive UIW RSS II first before getting into our more
detailed comparison.
| Key Specs | Definitive UIW RLS III | Definitive UIW RSS II |
|---|
| Brand | Definitive Technology
United States · founded 1990 | Definitive Technology
United States · founded 1990 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Hard-Dome | 1" Hard-Dome |
|---|
| Woofer | 2 x 5.25" Polypropylene | 2 x 4.5" Polypropylene |
|---|
| Frequency response | 24-30kHz | 26-30kHz |
|---|
| Sensitivity | 92 dB | 90 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 10-325 watts | 10-250 watts |
|---|
| Weight | — | 5.67kg / 12.5lbs |
|---|
| Dimensions (H x W x D) | 23.7500" x 5.8750" x 3.8750"
604.0 x 150.0 x 99.0mm | 11.6250" x 9.8750" x 3.8750"
296.0 x 251.0 x 99.0mm |
|---|
UIW RLS III and UIW RSS II are members of Definitive Technology's UIW series of speakers. Below you can find the loudspeakers from this series.
Definitive Technology UIW Series
History
What size room are the Definitive UIW RLS III and Definitive UIW RSS 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* |
Definitive UIW RLS III |
Definitive UIW RSS II |
| Near-field |
Are you nuts? |
Poor |
| Small Room |
Bad |
Poor |
| Mid-size Room |
Poor |
Good |
| Large Room |
Good |
Good |
| Very Large Room |
Good |
Average |
(* 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.
**This post contains affiliate links, and we will be compensated if you make a purchase after clicking
through our links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both UIW RLS III and UIW RSS II are 2-way speakers.
Definitive UIW RLS IIIDefinitive UIW RSS 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 |
Definitive UIW RLS III |
Definitive UIW RSS II |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5.25-inch
|
2 x 4.5-inch
|
UIW RLS III features a 1" Hard-Dome Tweeter and 2 x 5.25" Polypropylene Woofer. On the other hand, the UIW RSS II features a 1" Hard-Dome Tweeter and 2 x 4.5" Polypropylene Woofer.
Frequency Response
UIW RLS III has a frequency range of 24-30kHz whereas UIW RSS II has a frequency range of 26-30kHz. With a minimum frequency of 24Hz, the UIW RLS III can go slightly deeper then the UIW RSS II's min frequency of 26Hz.
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
UIW RLS III and UIW RSS II have the same Impedance of 8 ohms but where they differ is the sensitivity levels. UIW RLS III sensitivity is rated at 92 dB and the UIW RSS II's is at 90 dB. This 2 dB difference makes the Definitive UIW RLS III a more sensitive speaker compared to Definitive UIW RSS II, 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 III can handle a max power of 325 watts RMS, whereas UIW RSS II has a max power handling value of 250 watts RMS, 75 watts less than the UIW RLS III.
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
UIW RLS III features Spring pst type posts and UIW RSS II has a Spring pst 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 Definitive UIW RLS III's and Definitive UIW RSS II's external dimensions. Definitive UIW RLS III has external dimensions of 604.0 x 150.0 x 99.0mm (23.7500-inch x 5.8750-inch x 3.8750-inch) whereas Definitive UIW RSS II has external dimensions of 296.0 x 251.0 x 99.0mm (11.6250-inch x 9.8750-inch x 3.8750-inch).
What's in the Box of Definitive UIW RLS III?
Here are the items that are included inside the box of UIW RLS III:
- In-wall loudspeaker
- Grille
- Self-adhesive foam gasket
- Paint mask
- Wall-Mount Template
- Owners Manual
- Online Product Registration Card
What's in the Box of Definitive UIW RSS II?
Here are the items that come with the UIW RSS II:
- In-wall/In-cieling bipolar speaker
- Grille
- 7 Foam strips
- 2 Screws
- Paint mask
- Wall template
- Owners Manual
- Online Product Registration Card