In this review, we will be comparing R400 and Uni-Fi Reference UCR52, two Passive Center Channel speakers from Polk Audio and ELAC.
Let's have a brief look at the main features
of Polk R400 and ELAC Uni-Fi Ref UCR52 first before getting into our more
detailed comparison.
| Key Specs | Polk R400 | ELAC Uni-Fi Ref UCR52 |
|---|
| Brand | Polk Audio
United States · founded 1972 | ELAC
Germany · founded 1926 |
|---|
| Design | 2-way | 3-way |
|---|
| Tweeter | 1" Pinnacle Ring Radiator | 1" soft dome |
|---|
| Midrange | — | 4" |
|---|
| Woofer | 2 x 6.5" Polypropylene Turbine Cone | 2 x 5.25" aluminum |
|---|
| Frequency response | 48-39K Hz | 47-35k Hz |
|---|
| Sensitivity | 89 dB | 85 dB |
|---|
| Impedance | 8 ohms | 6 ohms |
|---|
| Power range | 20-200 watts | up to 140 watts |
|---|
| Weight | 14.91kg / 32.8lbs | 13.20kg / 29lbs |
|---|
| Dimensions (H x W x D) | 7-13/16" x 24-5/16" x 14-5/8"
199.0 x 618.0 x 372.0mm | 7-3/8" x 20-7/8" x 13-1/16"
188.0 x 531.0 x 332.0mm |
|---|
What size room are the Polk R400 and ELAC Uni-Fi Ref UCR52 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* |
Polk R400 |
ELAC Uni-Fi Ref UCR52 |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Average |
| 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.
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through our links. As an Amazon Associate I earn from qualifying purchases.
Drivers
One of the fundamental differences between these two speakers is that R400 is a 2-way design whereas the Uni-Fi Reference UCR52 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.
Polk R400ELAC Uni-Fi Ref UCR52
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Polk R400 |
ELAC Uni-Fi Ref UCR52 |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
1 x 4-inch |
|
Woofer
|
2 x 6.5-inch
|
2 x 5.25-inch
|
R400 features a 1" Pinnacle Ring Radiator Tweeter and 2 x 6.5" Polypropylene Turbine Cone Woofer with a Crossover frequency at 2500Hz. On the other hand, the Uni-Fi Reference UCR52 features a 1" soft dome Tweeter, a 4" Midrange and 2 x 5.25" aluminum Woofer.
Frequency Response
R400 has a frequency range of 48-39K Hz whereas Uni-Fi Reference UCR52 has a frequency range of 47-35k Hz. With a minimum frequency of 47Hz, the Uni-Fi Reference UCR52 can go slightly deeper then the R400's min frequency of 48Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Center Channel class in our database.
Low Frequency
Center Channel 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
R400 is a 8 ohms speaker compared to the Uni-Fi Reference UCR52 which has a nominal impedance of 6 ohms.
These two speakers also have different sensitivity levels. R400 sensitivity is rated at 89 dB and the Uni-Fi Reference UCR52's is rated at 85 dB. This 4 dB difference makes the Polk R400 a more sensitive speaker compared to ELAC Uni-Fi Ref UCR52, hence will play louder with the same amount of watts.
Sensitivity
Center Channel 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.
R400 can handle a max power of 200 watts RMS, whereas Uni-Fi Reference UCR52 has a max power handling value of 140 watts RMS, 60 watts less than the R400.
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
R400 features Binding post type posts and Uni-Fi Reference UCR52 has a Binding post type posts. None of these speakers feature bi-amping/bi-wiring.
Polk R400's Binding post terminals
ELAC Uni-Fi Ref UCR52's Binding post terminals
Cabinet Type and Port Position
R400 has a rear firing port whereas Uni-Fi Reference UCR52 has a front firing ports. ELAC Uni-Fi Ref UCR52's front-firing port gives more flexibility in placement in regards to proximity to walls compared to Polk R400 with its rear-firing port.
Polk R400 dual 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 Polk R400's and ELAC Uni-Fi Ref UCR52's external dimensions. Polk R400 has external dimensions of 199.0 x 618.0 x 372.0mm (7-13/16 x 24-5/16 x 14-5/8inch) whereas ELAC Uni-Fi Ref UCR52 has external dimensions of 188.0 x 531.0 x 332.0mm (7-3/8 x 20-7/8 x 13-1/16inch).
Polk R400 is clearly the larger of the two speakers. Its body is 87mm wider, 11mm taller and 40mm deeper than ELAC Uni-Fi Ref UCR52.
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 Polk R400 is approximately 2299.0cm2 / 356.3inch2 and base area of the ELAC Uni-Fi Ref UCR52 is approximately 1762.9cm2 / 273.2inch2. The R400 requires 30% more surface area than the Uni-Fi Reference UCR52 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 Polk R400 weighs 14.91kg / 32.8lbs and the ELAC Uni-Fi Ref UCR52 weighs 13.20kg / 29lbs. This makes the R400 13% heavier than the Uni-Fi Reference UCR52.
Here is a comparison of how R400 and Uni-Fi Reference UCR52's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
What's in the Box of Polk R400?
Here are the items that are included inside the box of R400:
- Center-channel loudspeaker
- Grille
- Owners Manual
- Online Registration
What's in the Box of ELAC Uni-Fi Ref UCR52?
Here are the items that come with the Uni-Fi Reference UCR52:
- Center-channel loudspeaker
- Grille
- 2 Jumper-bars (pre-installed)
- Operating Instructions
 Max Input Power |
200 watts
vs
140 watts
|
Handle more power from your amplifier |
 Sensitivity |
89 dB
vs
85 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
 High Frequency Response |
39k Hz
vs
35k Hz
|
Generates higher frequency |
 Price per pair* |
649USD
vs
700USD
|
costs less (*prices may change depending on the seller, location and time) |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
|
Low Frequency Response |
47 Hz
vs
48 Hz
|
Generates deeper bass |
 Port Position |
Front
vs
Rear
|
Gives more flexibility placing close to walls |
 Height |
188mm
vs
199mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1762cm2
vs
2299cm2
|
Takes less floor space |
| General |
Polk Audio Reserve R400 |
ELAC Uni-Fi Reference UCR52 |
| Brand |
Polk Audio |
ELAC |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
20-200 watts |
up to 140 watts |
| Sensitivity |
89 dB |
85 dB |
| Impedance |
8 ohms |
6 ohms |
| Impedance |
4.1 ohms |
n/a |
| Frequency Response |
48-39K Hz |
47-35k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
5.25" |
| Woofer Composition |
Polypropylene Turbine Cone |
aluminum |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Pinnacle Ring Radiator |
soft dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
4" |
| Crossover Frequency |
2500Hz |
n/a |
| Firing Direction |
rear |
front |
Physical Specs |
|
|
| Height |
199.0mm (7.8") |
188.0mm (7.4") |
| Width |
618.0mm (24.3") |
531.0mm (20.9") |
| Depth |
372.0mm (14.6") |
332.0mm (13.1") |
| Weight |
14.91kg (32.8lbs) |
13.20kg (29lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF/Wood-grain vinyl |
| Available Colors |
Black, Walnut |
Satin Black with Walnut Sides, Satin White with Oak Sides |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
n/a |
Other |
|
|
| Parts Warranty |
5 Years |
3 Years |
| Labor Warranty |
5 Years |
3 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 47Hz). |
| Amplifier needs | A | Polk R400 is more sensitive (89dB vs 85dB), so it goes louder on the same amplifier. |
| Amplifier match | A | Polk R400 is the easier load at 8 ohms. |
| Headroom | A | Polk R400 takes more power (200W vs 140W) - more in hand in a big room. |
| Size | depends | ELAC Uni-Fi Ref UCR52 is easier to place; Polk R400 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Polk R400 sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | evenly matched | Much the same money ($649 vs $700 a pair). |
A Polk R400 B ELAC Uni-Fi Ref UCR52
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?
Polk R400 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If your amplifier is modest, vintage or valve-based, Polk R400 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.