In this review, we will be comparing Airmotiv B1+ and R-51M, two Passive Bookshelf speakers from Emotiva and Klipsch.
Let's have a brief look at the main features
of Emotiva Airmotiv B1+ and Klipsch R-51M first before getting into our more
detailed comparison.
Emotiva Airmotiv B1+ Key Specs
- 2-way Design
- 25×32 mm" folded ribbon Tweeter
- 5.25" woven fiber cone Woofer
- 48 Hz – 28 kHz Frequency Response
- 86 dB Sensitivity
- Impedance: 8ohms
- Power Range:Up to 70watts
- Weight:4.00kg
- Dimensions (H x W x D): 274.0" x 7-1/8" x 8-1/4"( 274.0 x 181.0 x 210.0mm )
Klipsch R-51M Key Specs
- 2-way Design
- 1" Tractrix Horn Tweeter
- 5.25" Copper-spun IMG Woofer
- 62-21k Hz Frequency Response
- 93 dB Sensitivity
- Impedance: 8ohms
- Power Range:Up to 85watts
- Weight:5.00kg
- Dimensions (H x W x D): 338.0" x 7.0" x 8.4"( 338.0 x 178.0 x 215.0mm )
What size room are the Emotiva Airmotiv B1+ and Klipsch R-51M 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 B1+ |
Klipsch R-51M |
| Near-field |
Good |
Average |
| Small Room |
Good |
Good |
| Mid-size Room |
Average |
Average |
| Large Room |
Poor |
Poor |
| Very Large Room |
No way |
Bad |
(* 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 B1+ and Klipsch R-51M compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
**This post contains affiliate links, and I will be compensated if you make a purchase after clicking
through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both Airmotiv B1+ and R-51M are 2-way speakers.
| Driver |
Emotiva Airmotiv B1+ |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
25×32 mm-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 5.25-inch
|
Airmotiv B1+ features a 25×32 mm" folded ribbon Tweeter and 1 x 5.25" woven fiber cone Woofer with a Crossover frequency at 2000Hz. On the other hand, the R-51M features a 1" Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1660Hz.
Frequency Response
Airmotiv B1+ has a frequency range of 48 Hz – 28 kHz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 48Hz, the Airmotiv B1+ can go significantly deeper on the low side and provide stronger bass compared to the R-51M's min frequency of 62Hz.
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 Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf 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 B1+ and R-51M have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Airmotiv B1+ sensitivity is rated at 86 dB and the R-51M's is at 93 dB. This 7 dB difference makes the Klipsch R-51M a more sensitive speaker compared to Emotiva Airmotiv B1+, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf 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 B1+ can handle a max power of 85 watts RMS from the amp the whereas Airmotiv B1+ has a max power handling value of 70 watts RMS , 15 watts less than the R-51M.
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.
Cabinet Type and Port Position
Both Airmotiv B1+ and R-51M 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 B1+ 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 B1+'s and Klipsch R-51M's external dimensions. Emotiva Airmotiv B1+ has external dimensions of 274.0 x 181.0 x 210.0mm ( 10-3/4 x 7-1/8 x 8-1/4inch) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm ( 13.3 x 7.0 x 8.4inch) .
Emotiva Airmotiv B1+ is 64mm shorter and 5mm less deeper than Klipsch R-51M but it is also 3mm wider.
Below you can see the front view size comparison of Emotiva Airmotiv B1+ and Klipsch R-51M in scale.
Comparison image of Emotiva Airmotiv B1+ and Klipsch R-51M Size and External Dimensions
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 B1+ is approximately 380.1cm2 / 58.9inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The Airmotiv B1+ requires 1% less surface area than the R-51M which gives it a small advantage on placement in tight spaces.
Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:
Size Comparison image of Emotiva Airmotiv B1+ and Klipsch R-51M on a Media Console