In this review, we will be comparing R-51PM and A2+ Wireless, two Powered Bookshelf speakers from Klipsch and Audioengine. Being Powered speakers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features
of Klipsch R-51PM and Audioengine A2+ Wireless first before getting into our more
detailed comparison.
In the following sections, we will get into more detail in order to better understand how the Klipsch R-51PM and Audioengine A2+ Wireless 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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Drivers
Both R-51PM and A2+ Wireless are 2-way speakers.
| Driver |
Klipsch R-51PM |
Audioengine A2+ Wireless |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1.0-inch
|
0.75-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 2.75-inch
|
R-51PM features a 1.0" Aluminum LTS Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1663Hz. On the other hand, the A2+ Wireless features a 0.75" Silk Soft-Dome Tweeter and 1 x 2.75" Kevlar Woofer .
Frequency Response
R-51PM has a frequency range of 68-21k Hz whereas A2+ Wireless has a frequency range of 65-22k Hz. With a minimum frequency of 65Hz, the A2+ Wireless can go slightly deeper then the R-51PM's min frequency of 68Hz.
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.
Cabinet Type and Port Position
R-51PM has a rear firing port whereas A2+ Wireless has a front firing ports. Audioengine A2+ Wireless's front-firing port gives more flexibility in placement in regards to proximity to walls compared to Klipsch R-51PM with its rear-firing 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 Klipsch R-51PM's and Audioengine A2+ Wireless's external dimensions. Klipsch R-51PM has external dimensions of 330.2 x 179.4 x 260.3mm ( 13 x 7.0625 x 10.25inch) whereas Audioengine A2+ Wireless has external dimensions of 158.8 x 106.4 x 168.3mm ( 6.25 x 4.1875 x 6.625inch) .
Klipsch R-51PM is clearly the larger of the two speakers. Its body is 73mm wider, 171.4mm taller and 92mm deeper than Audioengine A2+ Wireless.
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 Klipsch R-51PM is approximately 467.0cm2 / 72.4inch2 and base area of the Audioengine A2+ Wireless is approximately 179.1cm2 / 27.8inch2. The R-51PM requires 161% more surface area than the A2+ Wireless which gives it a small disadvantage 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 Klipsch R-51PM weighs 4.80kg / 10.6lbs and the Audioengine A2+ Wireless weighs 1.40kg / 3.1lbs. This makes the R-51PM 243% heavier than the A2+ Wireless.
Here is a comparison of how R-51PM and A2+ Wireless's weights compare with the average, max and min weights in Powered Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Klipsch R-51PM?
Here are the items that are included inside the box of R-51PM:
Powered speaker (right)Passive speaker (left)2 Grilles68-inch AC power cordRemote control2
What's in the Box of Audioengine A2+ Wireless?
Here are the items that come with the A2+ Wireless:
Wireless powered left speakerPassive right speakerAC power supply (w/ attached 6-feet DC cord)6-feet AC power cord6.5-feet Length of 16 gauge speaker wire5-feet microUSB-to-USB cable6-feet Stereo minijack cable2 Cloth drawstring speaker pouches2 Cloth drawstring accessory pouchesQuick Start GuideAudioengine product brochure
 Woofer Size |
5.25 inches
vs
2.75 inches
|
Larger woofer |
 Handheld Remote |
Yes
vs
No
|
Control the speaker by the included RC |
 USB Port |
USB-B
vs
No
|
USB port adds flexibility |
 Phono Input |
Yes
vs
No
|
Connect your turntable directly |
 Digital Input |
Optical
vs
No
|
Connect digital inputs directly |
| Low Frequency Response |
65 Hz
vs
68 Hz
|
Generates deeper bass |
 High Frequency Response |
22k Hz
vs
21k Hz
|
Generates higher frequency |
 Port Position |
Front
vs
Rear
|
Gives more flexibility placing close to walls |
 Height |
158mm
vs
330mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
179cm2 (106x168mm)
vs
467cm2 (179x260mm)
|
Takes less floor space |
 Price per pair* |
269USD
vs
599USD
|
costs less (*prices may change depending on the seller, location and time) |
| USB Port |
microUSB
vs
No
|
USB port adds flexibility |
| General |
Klipsch Reference R-51PM |
Audioengine A2+ Wireless |
| Brand |
Klipsch |
Audioengine |
| Speaker Type |
Powered Stereo Speakers |
Powered Stereo Speakers |
| Frequency Response |
68-21k Hz |
65-22k Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
120-watt RMS |
30-watt RMS |
| Watts Peak (Max) |
240-watt RMS |
n/a |
| Max Bit Depth |
24-bit |
16-bit |
| Max Sample Rate |
96 kHz |
48 kHz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5.25" |
2.75" |
| Woofer Composition |
Copper-spun IMG |
Kevlar |
| Tweeter Size |
1.0" |
0.75" |
| Tweeter Type |
Tractrix Horn |
Soft-Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
1663Hz |
n/a |
| Firing Direction |
rear |
front |
Physical Specs |
|
|
| Height |
330.2mm (13") |
158.8mm (6.3") |
| Width |
179.4mm (7.1") |
106.4mm (4.2") |
| Depth |
260.3mm (10.2") |
168.3mm (6.6") |
| Weight |
4.80kg (10.6lbs) |
1.40kg (3.1lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Mounting Bracket |
No |
No |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Aux Inputs |
3.5mm, RCA |
3.5mm, RCA |
| USB Port |
USB-B |
microUSB |
| Phone Input |
Yes |
No |
| Subwoofer Output |
Wired |
Wired |
| Digital Input |
Optical |
No |
| HDMI Input |
No |
No |
| Headphone Jack |
No |
No |
| Ethernet Port |
No |
No |
Other |
|
|
| Parts Warranty |
1 Year |
3 Years |
| Labor Warranty |
1 Year |
3 Years |