In this review, we will be comparing Aria Evo X Center and RP-504C II, two Passive Center Channel speakers from Focal and Klipsch.
Let's have a brief look at the main features
of Focal Aria Evo X C and Klipsch RP-504C II first before getting into our more
detailed comparison.
| Key Specs | Focal Aria Evo X C | Klipsch RP-504C II |
|---|
| Brand | Focal
France · founded 1979 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" inverted dome | 1" Tractrix Horn |
|---|
| Woofer | 2 x 6.5" Flax | 4 x 5.25" Cerametallic cone |
|---|
| Frequency response | 57-30kHz | 50-25k Hz |
|---|
| Sensitivity | 91 dB | 96 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 40-120 watts | up to 150 watts |
|---|
| Weight | 10.50kg / 23.1lbs | 16.50kg / 36.3lbs |
|---|
| Dimensions (H x W x D) | 7-7/8" x 21" x 10"
20 x 53.3 x 24.5 cm | 6-15/16" x 32-3/16" x 15-1/8"
177.0 x 818.0 x 385.0mm |
|---|
What size room are the Focal Aria Evo X C and Klipsch RP-504C 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* |
Focal Aria Evo X C |
Klipsch RP-504C II |
| 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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Drivers
Both Aria Evo X Center and RP-504C II are 2-way speakers.
Focal Aria Evo X CKlipsch RP-504C 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 |
Focal Aria Evo X C |
Klipsch RP-504C II |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 6.5-inch
|
4 x 5.25-inch
|
Aria Evo X Center features a 1" Al/Mg inverted dome Tweeter and 2 x 6.5" Flax Woofer with a Crossover frequency at 2800 Hz. On the other hand, the RP-504C II features a 1" titanium Tractrix Horn Tweeter and 4 x 5.25" Cerametallic cone Woofer with a Crossover frequency at 1950 Hz.
Frequency Response
Aria Evo X Center has a frequency range of 57-30kHz whereas RP-504C II has a frequency range of 50-25k Hz. With a minimum frequency of 50Hz, the RP-504C II can go significantly deeper on the low side and provide stronger bass compared to the Aria Evo X Center's min frequency of 57Hz.
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
Aria Evo X Center and RP-504C II have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Aria Evo X Center sensitivity is rated at 91 dB and the RP-504C II's is at 96 dB. This 5 dB difference makes the Klipsch RP-504C II a more sensitive speaker compared to Focal Aria Evo X C, 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.
RP-504C II can handle a max power of 150 watts RMS, whereas Aria Evo X Center has a max power handling value of 120 watts RMS, 30 watts less than the RP-504C 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
Aria Evo X Center features Binding post posts which make bi-amping or bi-wiring possible. RP-504C II has a Binding post which doesn't feature bi-amping/bi-wiring.
Focal Aria Evo X C's Binding post terminals allows Bi-amping or bi-wiring
Klipsch RP-504C II's Binding post terminals
Cabinet Type and Port Position
Both Aria Evo X Center and RP-504C II have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
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 Focal Aria Evo X C's and Klipsch RP-504C II's external dimensions. Focal Aria Evo X C has external dimensions of 20 x 53.3 x 24.5 cm (7-7/8 x 21 x 9-5/8) whereas Klipsch RP-504C II has external dimensions of 177.0 x 818.0 x 385.0mm (6-15/16 x 32-3/16 x 15-1/8inch).
Focal Aria Evo X C is 285mm narrower and 140mm less deeper than Klipsch RP-504C II but it is also 23mm taller.
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 Focal Aria Evo X C is approximately 1305.9cm2 / 202.4inch2 and base area of the Klipsch RP-504C II is approximately 3149.3cm2 / 488.1inch2. The Aria Evo X Center requires 59% less surface area than the RP-504C II which gives it a small advantage 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 Focal Aria Evo X C weighs 10.50kg / 23.1lbs and the Klipsch RP-504C II weighs 16.50kg / 36.3lbs. This makes the RP-504C II 57% heavier than the Aria Evo X Center.
Here is a comparison of how Aria Evo X Center and RP-504C II'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 Klipsch RP-504C II?
Here are the items that come with the RP-504C II:
- Center channel loudspeaker
- Grille
- User Manual
- Important Safety Instructions
- Warranty Information
 Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
 High Frequency Response |
30k Hz
vs
25k Hz
|
Generates higher frequency |
 Bi-Amping and Bi-Wiring |
Yes
vs
No
|
Allows bi-amping and bi-wiring connections |
 Base Surface Area |
1305cm2
vs
3149cm2
|
Takes less floor space |
 Max Input Power |
150 watts
vs
120 watts
|
Handle more power from your amplifier |
 Sensitivity |
96 dB
vs
91 dB
|
Play louder with same amount of amplification power |
|
Number of Woofers |
4
vs
2
|
More woofers |
|
Low Frequency Response |
50 Hz
vs
57 Hz
|
Generates deeper bass |
 Height |
177mm
vs
200mm
|
Easier to fit in smaller spaces |
 Price per pair* |
799USD
vs
999USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Focal Aria Evo X Center |
Klipsch Reference Premiere RP-504C II |
| Brand |
Focal |
Klipsch |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
40-120 watts |
up to 150 watts |
| Sensitivity |
91 dB |
96 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
4.3 ohms |
n/a |
| Frequency Response |
57-30kHz |
50-25k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
4 |
| Woofer Size |
6.5" |
5.25" |
| Woofer Composition |
Flax |
Cerametallic cone |
| Woofer Surround Material |
TMD |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
inverted dome |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2800 Hz |
1950 Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
200.0mm (7.9") |
177.0mm (7") |
| Width |
533.0mm (21") |
818.0mm (32.2") |
| Depth |
245.0mm (9.6") |
385.0mm (15.2") |
| Weight |
10.50kg (23.1lbs) |
16.50kg (36.3lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF/Wood-grain vinyl |
| Available Colors |
Black High Gloss, Prime Walnut, Moss Green High Gloss |
Walnut, Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
No |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 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 | B | Klipsch RP-504C II digs deeper - 50Hz against 57Hz. A subwoofer would even that out. |
| Amplifier needs | B | Klipsch RP-504C II is more sensitive (96dB vs 91dB), so it goes louder on the same amplifier. |
| Headroom | B | Klipsch RP-504C II takes more power (150W vs 120W) - more in hand in a big room. |
| Size | depends | Focal Aria Evo X C is easier to place; Klipsch RP-504C II is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Focal Aria Evo X C: bi-amping. Klipsch RP-504C II sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | B | Klipsch RP-504C II is cheaper - $799 against $999, about 20% less. |
A Focal Aria Evo X C B Klipsch RP-504C II
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?
Klipsch RP-504C II is the easier recommendation: it leads on most of the measured areas and costs less. Take Focal Aria Evo X C if its size, looks or fit in your room suit you better. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 57Hz anyway, so judge these on the other rows instead. In a large or open-plan room, Klipsch RP-504C II has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Focal Aria Evo X C is the easier speaker to get right.
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.