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  1. Home
  2. Passive In-wall Speakers
  3. Definitive DI 6.5LCR vs Definitive UIW RLS III

Definitive DI 6.5LCR vs Definitive UIW RLS III Comparison

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Definitive DI 6.5LCR

Passive In-wall | 26-30kHz

Definitive DI 6.5LCR
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Definitive UIW RLS III

Passive In-wall | 24-30kHz

Definitive Technology UIW RLS III
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Definitive DI 6.5LCR Definitive DI 6.5LCR
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Definitive UIW RLS III Definitive UIW RLS I...
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Definitive DI 6.5LCR
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Definitive UIW RLS I...
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Definitive DI 6.5LCR vs Definitive UIW RLS III Speaker Comparison

In this review, we will be comparing DI 6.5LCR and UIW RLS III, two Passive In-wall speakers by Definitive Technology.

Let's have a brief look at the main features of Definitive DI 6.5LCR and Definitive UIW RLS III first before getting into our more detailed comparison.

Key SpecsDefinitive DI 6.5LCRDefinitive UIW RLS III
BrandDefinitive Technology
United States · founded 1990
Definitive Technology
United States · founded 1990
Design2-way2-way
Tweeter1" Hard-Dome1" Hard-Dome
Woofer2 x 6.5" Polymer2 x 5.25" Polypropylene
Frequency response26-30kHz24-30kHz
Sensitivity90 dB92 dB
Impedance8 ohms8 ohms
Power range10-275 watts10-325 watts
Dimensions (H x W x D)16.1875" x 7.3125" x 3.6250"
412.0 x 186.0 x 93.0mm
23.7500" x 5.8750" x 3.8750"
604.0 x 150.0 x 99.0mm

What size room are the Definitive DI 6.5LCR and Definitive UIW RLS III 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 DI 6.5LCR Definitive UIW RLS III
Near-field Poor Are you nuts?
Small Room Poor Bad
Mid-size Room Good Poor
Large Room Good Good
Very Large Room Average 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.


**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 DI 6.5LCR and UIW RLS III are 2-way speakers.

Tweeter - 1 inchWoofer - 6.5 inchWoofer - 6.5 inch
Definitive DI 6.5LCR
Tweeter - 1 inchWoofer - 5.25 inchWoofer - 5.25 inch
Definitive UIW RLS III

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 DI 6.5LCR Definitive UIW RLS III
Driver Setup 2-way 2-way
Tweeter 1-inch 1-inch
Midrange - -
Woofer 2 x 6.5-inch 2 x 5.25-inch

DI 6.5LCR features a 1" Hard-Dome Tweeter and 2 x 6.5" Polymer Woofer. On the other hand, the UIW RLS III features a 1" Hard-Dome Tweeter and 2 x 5.25" Polypropylene Woofer.

Frequency Response

DI 6.5LCR has a frequency range of 26-30kHz whereas UIW RLS III has a frequency range of 24-30kHz. With a minimum frequency of 24Hz, the UIW RLS III can go slightly deeper then the DI 6.5LCR'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

DI 6.5LCR
UIW RLS III
Min
Average
Median

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

DI 6.5LCR and UIW RLS III have the same Impedance of 8 ohms but where they differ is the sensitivity levels. DI 6.5LCR sensitivity is rated at 90 dB and the UIW RLS III's is at 92 dB. This 2 dB difference makes the Definitive UIW RLS III a more sensitive speaker compared to Definitive DI 6.5LCR, hence will play louder with the same amount of watts.

Sensitivity

In-wall Speakers

DI 6.5LCR
UIW RLS III
Min
Average
Median

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 DI 6.5LCR has a max power handling value of 275 watts RMS, 50 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.

Definitive DI 6.5LCR
 
Definitive UIW RLS III
 

Input Type and Bi-Amping / Bi-Wiring

DI 6.5LCR features Spring post type posts and UIW RLS III 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 Definitive DI 6.5LCR's and Definitive UIW RLS III's external dimensions. Definitive DI 6.5LCR has external dimensions of 412.0 x 186.0 x 93.0mm (16.1875-inch x 7.3125-inch x 3.6250-inch) whereas 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).

Definitive DI 6.5LCR is 192mm shorter and 6mm less deeper than Definitive UIW RLS III but it is also 36mm wider.

What's in the Box of Definitive DI 6.5LCR?

Here are the items that are included inside the box of DI 6.5LCR:
  • Dual 6.5

What's in the Box of Definitive UIW RLS III?

Here are the items that come with the UIW RLS III:
  • In-wall loudspeaker
  • Grille
  • Self-adhesive foam gasket
  • Paint mask
  • Wall-Mount Template
  • Owners Manual
  • Online Product Registration Card


Reasons to choose Definitive DI 6.5LCR over Definitive Technology UIW RLS III

Woofer Size 6.5 inches vs 5.25 inches Larger woofer
Height 412mm vs 604mm Easier to fit in smaller spaces
Price per pair* 1198USD vs 1398USD costs less (*prices may change depending on the seller, location and time)

Reasons to choose Definitive Technology UIW RLS III over Definitive DI 6.5LCR

Max Input Power 325 watts vs 275 watts Handle more power from your amplifier
Sensitivity 92 dB vs 90 dB Play louder with same amount of amplification power
Low Frequency Response 24 Hz vs 26 Hz Generates deeper bass
Passive Radiator 2 x 5.25-inch vs None Increases the bass performance
Base Surface Area 148cm2 vs 173cm2 Takes less floor space

Definitive DI 6.5LCR vs Definitive UIW RLS III Specs Table

Detailed comparison of specifications
General Definitive DI 6.5LCR Definitive Technology UIW RLS III
Brand Definitive Technology Definitive Technology
Speaker Type Passive In-wall Speaker Passive In-wall Speaker
Power Range 10-275 watts 10-325 watts
Sensitivity 90 dB 92 dB
Impedance 8 ohms 8 ohms
Frequency Response 26-30kHz 24-30kHz
Drivers
Woofer Quantity 2 2
Woofer Size 6.5" 5.25"
Woofer Composition Polymer Polypropylene
Woofer Surround Material Rubber Butyl Rubber
Tweeter Size 1" 1"
Tweeter Type Hard-Dome Hard-Dome
Aimable Tweeter No No
Midrange Driver No No
Physical Specs
Height 412.0mm (16.2") 604.0mm (23.8")
Width 186.0mm (7.3") 150.0mm (5.9")
Depth 93.0mm (3.7") 99.0mm (3.9")
Enclosure In-wall In-wall
Moisture Resistancy No Yes
Connections
Biamp Inputs No No
Other
Parts Warranty 5 Years 5 Years
Labor Warranty 5 Years 5 Years

Verdict

Both are Definitive Technology, from different ranges - so the house sound is shared and the differences are mostly in scale, engineering and price.

AreaBetterWhy
Bassevenly matchedMuch the same reach (26Hz vs 24Hz).
Amplifier needsBDefinitive UIW RLS III is more sensitive (92dB vs 90dB), so it goes louder on the same amplifier.
Headroomevenly matchedSimilar power handling (275W vs 325W).
SizedependsDefinitive DI 6.5LCR is easier to place; Definitive UIW RLS III is bigger, which usually goes with fuller bass. Your room decides.
PriceADefinitive DI 6.5LCR is cheaper - $1,198 against $1,398, about 14% less.

A Definitive DI 6.5LCR  B Definitive UIW RLS III
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?

The usual trade-off: Definitive UIW RLS III measures better, Definitive DI 6.5LCR costs about about 17% more% less. Whether that gap is worth the money is the call only you can make - and in a normal room it is often smaller than the numbers suggest. Match it to your room: we rate Definitive DI 6.5LCR the better fit for a mid-size room, and Definitive UIW RLS III for a very large room. If your amplifier is modest, vintage or valve-based, Definitive UIW RLS III is the safer partner - the other will want more current or more watts to sound its best.

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.


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