In this review, we will be comparing Alpha AM3 and R-51PM, two Powered Bookshelf speakers from PSB and Klipsch. 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 PSB Alpha AM3 and Klipsch R-51PM first before getting into our more
detailed comparison.
PSB Alpha AM3 Key Specs
- 2-way Design
- 70-watt RMS Integrated Amplifier
- 0.75" Hard-Dome Tweeter
- 4" Polypropylene Woofer
- 56-20k Hz Frequency Response
- 24-bit Max Depth / 48 kHz Max Sample Rate
- Built-in 5.0 Bluetooth
- Weight:4.50kg
- Dimensions (H x W x D): 220.7" x 5.1875" x 8.125"( 220.7 x 131.8 x 206.4mm )
Klipsch R-51PM Key Specs
- 2-way Design
- 120-watt RMS( 240-watt Peak) Integrated Amplifier
- 1.0" Tractrix Horn Tweeter
- 5.25" Copper-spun IMG Woofer
- 68-21k Hz Frequency Response
- 24-bit Max Depth / 96 kHz Max Sample Rate
- Built-in 3.0 Bluetooth
- Weight:4.80kg
- Dimensions (H x W x D): 330.2" x 7.0625" x 10.25"( 330.2 x 179.4 x 260.3mm )
In the following sections, we will get into more detail in order to better understand how the PSB Alpha AM3 and Klipsch R-51PM 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 Alpha AM3 and R-51PM are 2-way speakers.
| Driver |
PSB Alpha AM3 |
Klipsch R-51PM |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
0.75-inch
|
1.0-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 4-inch
|
1 x 5.25-inch
|
Alpha AM3 features a 0.75" Aluminum Hard-Dome Tweeter and 1 x 4" Polypropylene Woofer . On the other hand, the 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.
Frequency Response
Alpha AM3 has a frequency range of 56-20k Hz whereas R-51PM has a frequency range of 68-21k Hz. With a minimum frequency of 56Hz, the Alpha AM3 can go significantly deeper on the low side and provide stronger bass compared to 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
Both Alpha AM3 and R-51PM 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 PSB Alpha AM3's and Klipsch R-51PM's external dimensions. PSB Alpha AM3 has external dimensions of 220.7 x 131.8 x 206.4mm ( 8.6875 x 5.1875 x 8.125inch) whereas Klipsch R-51PM has external dimensions of 330.2 x 179.4 x 260.3mm ( 13 x 7.0625 x 10.25inch) .
Klipsch R-51PM is clearly the larger of the two speakers. Its body is 47.6mm wider, 109.5mm taller and 53.9mm deeper than PSB Alpha AM3.
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 PSB Alpha AM3 is approximately 272.0cm2 / 42.2inch2 and base area of the Klipsch R-51PM is approximately 467.0cm2 / 72.4inch2. The Alpha AM3 requires 42% less surface area than the R-51PM 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 PSB Alpha AM3 weighs 4.50kg / 9.9lbs and the Klipsch R-51PM weighs 4.80kg / 10.6lbs. This makes the R-51PM 7% heavier than the Alpha AM3.
Here is a comparison of how Alpha AM3 and R-51PM's weights compare with the average, max and min weights in Powered Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of PSB Alpha AM3?
Here are the items that are included inside the box of Alpha AM3:
Powered speaker Passive speaker 2 Grilles AC power adapter (attached 45-inch DC cord) 4-feet AC power cord Remote control (PSR-1) 2 AAA batteries 8-feet Speaker cable 58-inch Stereo minijack cable 8 Self-adhesive rubber feet Connection Diagram Warranty Card
What's in the Box of Klipsch R-51PM?
Here are the items that come with the R-51PM:
Powered speaker (right)Passive speaker (left)2 Grilles68-inch AC power cordRemote control2