In this review, we will be comparing AE307 and Airmotiv C2+, two Passive Center Channel speakers from Acoustic Energy and Emotiva.
Let's have a brief look at the main features
of AE307 and Emotiva Airmotiv C2+ first before getting into our more
detailed comparison.
| Key Specs | AE307 | Emotiva Airmotiv C2+ |
|---|
| Brand | Acoustic Energy
United Kingdom · founded 1987 | Emotiva
United States · founded 2003 |
|---|
| Design | 2-way | 3-way |
|---|
| Tweeter | 1.1" dome with waveguide | 25×32 mm" folded ribbon |
|---|
| Midrange | — | 2 x 3" |
|---|
| Woofer | 2 x 5.2" ceramic aluminium sandwich | 2 x 6.5" woven fiber cone |
|---|
| Frequency response | 42Hz - 30kHz | 45 Hz – 28 kHz |
|---|
| Sensitivity | 89 dB | 92 dB |
|---|
| Impedance | 6 ohms | 4 ohms |
|---|
| Power range | up to 175 watts | Up to 150 watts |
|---|
| Weight | 9.00kg / 19.8lbs | 16.40kg / 36.1lbs |
|---|
| Dimensions (H x W x D) | 6.9" x 18.1" x 10.2"
175.0 x 460.0 x 260.0mm | 8-5/8" x 31-15/16" x 10-1/2"
220.0 x 812.0 x 267.0mm |
|---|
What size room are the AE307 and Emotiva Airmotiv C2+ 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* |
AE307 |
Emotiva Airmotiv C2+ |
| 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.
Drivers
One of the fundamental differences between these two speakers is that AE307 is a 2-way design whereas the Airmotiv C2+ 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.
AE307Emotiva Airmotiv C2+
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
AE307 |
Emotiva Airmotiv C2+ |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1.1-inch
|
25×32 mm-inch
|
|
Midrange
|
- |
2 x 3-inch |
|
Woofer
|
2 x 5.2-inch
|
2 x 6.5-inch
|
AE307 features a 1.1" aluminium dome with waveguide Tweeter and 2 x 5.2" ceramic aluminium sandwich Woofer with a Crossover frequency at 2560Hz. On the other hand, the 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.
Frequency Response
AE307 has a frequency range of 42Hz - 30kHz whereas Airmotiv C2+ has a frequency range of 45 Hz – 28 kHz. With a minimum frequency of 42Hz, the AE307 can go slightly deeper then the Airmotiv C2+'s min frequency of 45Hz.
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
AE307 is a 6 ohms speaker compared to the Airmotiv C2+ which has a nominal impedance of 4 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. AE307 sensitivity is rated at 89 dB and the Airmotiv C2+'s is rated at 92 dB. This 3 dB difference makes the Emotiva Airmotiv C2+ a more sensitive speaker compared to AE307, 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.
AE307 can handle a max power of 175 watts RMS, whereas Airmotiv C2+ has a max power handling value of 150 watts RMS, 25 watts less than the AE307.
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.
Cabinet Type and Port Position
Both AE307 and Airmotiv C2+ 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
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 AE307's and Emotiva Airmotiv C2+'s external dimensions. AE307 has external dimensions of 175.0 x 460.0 x 260.0mm (6.9 x 18.1 x 10.2inch) whereas 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).
Emotiva Airmotiv C2+ is clearly the larger of the two speakers. Its body is 352mm wider, 45mm taller and 7mm deeper than AE307.
Size, drawn to scale
Both speakers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same surface and pushed back to the same wall, so the deeper one visibly sticks out further.
Emotiva Airmotiv C2+ needs about 81% more floor or shelf area. Emotiva Airmotiv C2+ is 45mm 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 AE307 is approximately 1196.0cm2 / 185.4inch2 and base area of the Emotiva Airmotiv C2+ is approximately 2168.0cm2 / 336.0inch2. The AE307 requires 45% less surface area than the Airmotiv C2+ 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 AE307 weighs 9.00kg / 19.8lbs and the Emotiva Airmotiv C2+ weighs 16.40kg / 36.1lbs. This makes the Airmotiv C2+ 82% heavier than the AE307.
Here is a comparison of how AE307 and Airmotiv C2+'s weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
 Max Input Power |
175 watts
vs
150 watts
|
Handle more power from your amplifier |
 Nominal Impedance |
6 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Low Frequency Response |
42 Hz
vs
45 Hz
|
Generates deeper bass |
 High Frequency Response |
30k Hz
vs
28k Hz
|
Generates higher frequency |
 Height |
175mm
vs
220mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1196cm2
vs
2168cm2
|
Takes less floor space |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 Sensitivity |
92 dB
vs
89 dB
|
Play louder with same amount of amplification power |
|
Woofer Size |
6.5 inches
vs
5.2 inches
|
Larger woofer |
 Price per pair* |
499USD
vs
799USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Acoustic Energy AE307 |
Emotiva Airmotiv C2+ |
| Brand |
Acoustic Energy |
Emotiva |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
up to 175 watts |
Up to 150 watts |
| Sensitivity |
89 dB |
92 dB |
| Impedance |
6 ohms |
4 ohms |
| Frequency Response |
42Hz - 30kHz |
45 Hz – 28 kHz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5.2" |
6.5" |
| Woofer Composition |
ceramic aluminium sandwich |
woven fiber cone |
| Tweeter Size |
1.1" |
25×32 mm" |
| Tweeter Type |
dome with waveguide |
folded ribbon |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
3" |
| Crossover Frequency |
2560Hz |
350 Hz and 3200Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
175.0mm (6.9") |
220.0mm (8.7") |
| Width |
460.0mm (18.1") |
812.0mm (32") |
| Depth |
260.0mm (10.2") |
267.0mm (10.5") |
| Weight |
9.00kg (19.8lbs) |
16.40kg (36.1lbs) |
| Enclosure |
Bass Reflex |
Bass reflex |
| Finish |
high density MDF |
HDF |
| Available Colors |
Piano Gloss White, Piano Gloss Black, Real Walnut wood veneer |
Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
n/a |
Yes |
Other |
|
|
| Parts Warranty |
|
5 Years |
| Labor Warranty |
|
5 Years |
These sit in different price classes - AE307 costs roughly 1.6x what Emotiva Airmotiv C2+ does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | A | AE307 digs deeper - 42Hz against 45Hz. A subwoofer would even that out. |
| Amplifier needs | B | Emotiva Airmotiv C2+ is more sensitive (92dB vs 89dB), so it goes louder on the same amplifier. |
| Amplifier match | A | AE307 is the easier load at 6 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | evenly matched | Similar power handling (175W vs 150W). |
| Size | depends | AE307 is easier to place; Emotiva Airmotiv C2+ is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | B | Emotiva Airmotiv C2+: bi-amping. Emotiva Airmotiv C2+ sits in a wider range (9 models), so a matched surround system is easier later. |
| Price | B | Emotiva Airmotiv C2+ is cheaper - $499 against $799, about 38% less; arguably a different class. |
A AE307 B Emotiva Airmotiv C2+
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and your own room settle it. In a large or open-plan room, Emotiva Airmotiv C2+ has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, AE307 is the easier speaker to get right. If your amplifier is modest, vintage or valve-based, Emotiva Airmotiv C2+ 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.