In this review, we will be comparing AE100 MII and R-51M, two Passive Bookshelf speakers from Acoustic Energy and Klipsch.
Let's have a brief look at the main features
of AE100 Mark II and Klipsch R-51M first before getting into our more
detailed comparison.
AE100 Mark II Key Specs
- 2-way Design
- 1" soft dome with waveguide Tweeter
- 5.2" paper cone Woofer
- 51Hz - 26kHz Frequency Response
- 87 dB Sensitivity
- Impedance: 6ohms
- Power Range:up to 120watts
- Weight:4.60kg
- Dimensions (H x W x D): 290.0" x 6.5" x 9.8"( 290.0 x 165.0 x 250.0mm )
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 AE100 Mark II 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* |
AE100 Mark II |
Klipsch R-51M |
| Near-field |
Poor |
Average |
| Small Room |
Average |
Good |
| Mid-size Room |
Good |
Average |
| Large Room |
Average |
Poor |
| Very Large Room |
Poor |
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 AE100 Mark II 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.
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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both AE100 MII and R-51M are 2-way speakers.
| Driver |
AE100 Mark II |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.2-inch
|
1 x 5.25-inch
|
AE100 MII features a 1" fabric soft dome with waveguide Tweeter and 1 x 5.2" paper cone Woofer with a Crossover frequency at 2900Hz. 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
AE100 MII has a frequency range of 51Hz - 26kHz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 51Hz, the AE100 MII 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
AE100 MII is a 6 ohms speaker compared to the R-51M which has a nominal impedance of 8 ohms.
These two speakers also have different sensitivity levels. AE100 MII sensitivity is rated at 87 dB and the R-51M's is rated at 93 dB. This 6 dB difference makes the Klipsch R-51M a more sensitive speaker compared to AE100 Mark II, 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.
AE100 MII can handle a max power of 120 watts RMS from the amp the whereas R-51M has a max power handling value of 85 watts RMS, 35 watts less than the AE100 MII.
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 AE100 MII 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.
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 AE100 Mark II's and Klipsch R-51M's external dimensions. AE100 Mark II has external dimensions of 290.0 x 165.0 x 250.0mm ( 11.4 x 6.5 x 9.8inch) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm ( 13.3 x 7.0 x 8.4inch) .
AE100 Mark II is 13mm narrower and 48mm shorter than Klipsch R-51M but it is also 35mm 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 AE100 Mark II is approximately 412.5cm2 / 63.9inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The AE100 MII requires 8% more surface area than the R-51M which gives it a small disadvantage on placement in tight spaces.