In this review, we will be comparing UIW RSS III and IW Sub Reference, two Passive In-wall speakers by Definitive Technology
Let's have a brief look at the main features
of Definitive UIW RSS III and Definitive IW Sub Reference first before getting into our more
detailed comparison.
Definitive UIW RSS III Key Specs
- 2-way Design
- 1" Hard-Dome Tweeter
- 2 x 3.5" Polypropylene Woofer
- 40-30kHz Frequency Response
- 90 dB Sensitivity
- Impedance: 8ohms
- Power Range:10-200watts
- Dimensions (H x W x D): 251.0" x 8.3750" x 3.8750"( 251.0 x 213.0 x 99.0mm )
Definitive IW Sub Reference Key Specs
- 1-way Design
- " Tweeter
- 13" Not given Woofer
- 14-200Hz Frequency Response
- Impedance: 4ohms
- Power Range:up to 275watts
- Dimensions (H x W x D): 639.0" x 14.3750" x 4.0000"( 639.0 x 366.0 x 102.0mm )
What size room are the Definitive UIW RSS III and Definitive IW Sub Reference 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 RSS III |
Definitive IW Sub Reference |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Poor |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Good |
| Very Large Room |
Poor |
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.)
In the following sections, we will get into more detail in order to better understand how the Definitive UIW RSS III and Definitive IW Sub Reference compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
**This post contains affiliate links, and I will be compensated if you make a purchase after clicking
through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
One of the fundamental differences between these two speakers is that UIW RSS III is a 2-way design whereas the IW Sub Reference is a 1-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.
| Driver |
Definitive UIW RSS III |
Definitive IW Sub Reference |
|
Driver Setup
|
2-way
|
1-way
|
|
Tweeter
|
1-inch
|
-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 3.5-inch
|
1 x 13-inch
|
UIW RSS III features a 1" Hard-Dome Tweeter and 2 x 3.5" Polypropylene Woofer . On the other hand, the IW Sub Reference features a " Tweeter and 1 x 13" Not given Woofer .
Frequency Response
UIW RSS III has a frequency range of 40-30kHz whereas IW Sub Reference has a frequency range of 14-200Hz. With a minimum frequency of 14Hz, the IW Sub Reference can go significantly deeper on the low side and provide stronger bass compared to the UIW RSS III's min frequency of 40Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the In-wall class in our database.
Low Frequency
In-wall Speakers
High Frequency
In-wall Speakers
Definitive IW Sub Reference
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using
an amplifier within this range ensures the nominal performance , inputting a power that is higher than the
max wattage can result in a damaged speaker.
UIW RSS III can handle a max power of 275 watts RMS from the amp the whereas UIW RSS III has a max power handling value of 200 watts RMS , 75 watts less than the IW Sub Reference.
Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker
compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters
such as Impedance, sensitivity and system efficiencies.
Input Type and Bi-Amping / Bi-Wiring
UIW RSS III features Spring post type posts and IW Sub Reference has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.
Physical Specs
Size of a speaker can sometimes become 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 RSS III's and Definitive IW Sub Reference's external dimensions. Definitive UIW RSS III has external dimensions of 251.0 x 213.0 x 99.0mm ( 9.8750-inch x 8.3750-inch x 3.8750-inch) whereas Definitive IW Sub Reference has external dimensions of 639.0 x 366.0 x 102.0mm ( 25.1250-inch x 14.3750-inch x 4.0000-inch) .
Definitive IW Sub Reference is clearly the larger of the two speakers. Its body is 153mm wider, 388mm taller and 3mm deeper than Definitive UIW RSS III.
What's in the Box of Definitive UIW RSS III?
Here are the items that are included inside the box of UIW RSS III:
In-wall/In-cieling bipolar speakerGrille7 Foam strips2 ScrewsPaint maskWall templateOwners ManualOnline Product Registration Card
What's in the Box of Definitive IW Sub Reference?
Here are the items that come with the IW Sub Reference:
In-wall subwooferGrille (attached)4 Long self-adhesive foam gaskets3 Short self-adhesive foam gaskets8 ScrewsWall-templatePaint maskOwners ManualOnline Product Registration card