In this review, we will be comparing Airmotiv C2+ and R400, two Passive Center Channel speakers from Emotiva and Polk Audio.
Let's have a brief look at the main features
of Emotiva Airmotiv C2+ and Polk R400 first before getting into our more
detailed comparison.
Emotiva Airmotiv C2+ Key Specs
- 3-way Design
- 25×32 mm" folded ribbon Tweeter
- 3" Midrange
- 2 x 6.5" woven fiber cone Woofer
- 45 Hz – 28 kHz Frequency Response
- 92 dB Sensitivity
- Impedance: 4ohms
- Power Range:Up to 150watts
- Weight:16.40kg
- Dimensions (H x W x D): 220.0" x 31-15/16" x 10-1/2"( 220.0 x 812.0 x 267.0mm )
Polk R400 Key Specs
- 2-way Design
- 1" Pinnacle Ring Radiator Tweeter
- 2 x 6.5" Polypropylene Turbine Cone Woofer
- 48-39K Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-200watts
- Weight:14.91kg
- Dimensions (H x W x D): 199.0" x 24-5/16" x 14-5/8"( 199.0 x 618.0 x 372.0mm )
What size room are the Emotiva Airmotiv C2+ and Polk R400 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* |
Emotiva Airmotiv C2+ |
Polk R400 |
| 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.)
In the following sections, we will get into more detail in order to better understand how the Emotiva Airmotiv C2+ and Polk R400 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
One of the fundamental differences between these two speakers is that Airmotiv C2+ is a 3-way design whereas the R400 is a 2-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 |
Emotiva Airmotiv C2+ |
Polk R400 |
|
Driver Setup
|
3-way
|
2-way
|
|
Tweeter
|
25×32 mm-inch
|
1-inch
|
|
Midrange
|
2 x 3-inch |
- |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
Airmotiv C2+ features a 25×32 mm" folded ribbon Tweeter , a 3" Midrange and 2 x 6.5" woven fiber cone Woofer with a Crossover frequency at 350 Hz and 3200Hz. On the other hand, the R400 features a 1" Pinnacle Ring Radiator Tweeter and 2 x 6.5" Polypropylene Turbine Cone Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Airmotiv C2+ has a frequency range of 45 Hz – 28 kHz whereas R400 has a frequency range of 48-39K Hz. With a minimum frequency of 45Hz, the Airmotiv C2+ can go slightly deeper then the R400's min frequency of 48Hz.
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 Center Channel class in our database.
Low Frequency
Center Channel Speakers
High Frequency
Center Channel Speakers
None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
Airmotiv C2+ is a 4 ohms speaker compared to the R400 which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the Airmotiv C2+ can provide this impedance level.
These two speakers also have different sensitivity levels. Airmotiv C2+ sensitivity is rated at 92 dB and the R400's is rated at 89 dB. This 3 dB difference makes the Emotiva Airmotiv C2+ a more sensitive speaker compared to Polk R400, 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. 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.
Airmotiv C2+ can handle a max power of 200 watts RMS from the amp the whereas Airmotiv C2+ has a max power handling value of 150 watts RMS , 50 watts less than the R400.
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
Airmotiv C2+ features Binding post posts which make bi-amping or bi-wiring possible. R400 has a Binding post which doesn't feature bi-amping/bi-wiring.
Emotiva Airmotiv C2+'s Binding post terminals allows Bi-amping or bi-wiring
Polk R400's Binding post terminals
Cabinet Type and Port Position
Both Airmotiv C2+ and R400 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.
Emotiva Airmotiv C2+ Port
Polk R400 dual Port
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 Emotiva Airmotiv C2+'s and Polk R400's external dimensions. Emotiva Airmotiv C2+ has external dimensions of 220.0 x 812.0 x 267.0mm ( 8-5/8 x 31-15/16 x 10-1/2inch) whereas 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) .
Polk R400 is 194mm narrower and 21mm shorter than Emotiva Airmotiv C2+ but it is also 105mm deeper.
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 Emotiva Airmotiv C2+ is approximately 2168.0cm2 / 336.0inch2 and base area of the Polk R400 is approximately 2299.0cm2 / 356.3inch2. The Airmotiv C2+ requires 6% less surface area than the R400 which gives it a small advantage on placement in tight spaces.