In this review, we will be comparing R-51M and RTi A3, two Passive Bookshelf speakers from Klipsch and Polk Audio.
Let's have a brief look at the main features
of Klipsch R-51M and Polk RTi A3 first before getting into our more
detailed comparison.
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 )
Polk RTi A3 Key Specs
- 2-way Design
- 1" Dome Tweeter
- 6.5" Polymer composite Woofer
- 50-26k Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:20-150watts
- Weight:7.26kg
- Dimensions (H x W x D): 374.7" x 8.4" x 14.0"( 374.7 x 214.4 x 355.6mm )
What size room are the Klipsch R-51M and Polk RTi A3 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* |
Klipsch R-51M |
Polk RTi A3 |
| Near-field |
Average |
Poor |
| Small Room |
Good |
Average |
| Mid-size Room |
Average |
Good |
| Large Room |
Poor |
Average |
| Very Large Room |
Bad |
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.)
In the following sections, we will get into more detail in order to better understand how the Klipsch R-51M and Polk RTi A3 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 R-51M and RTi A3 are 2-way speakers.
| Driver |
Klipsch R-51M |
Polk RTi A3 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 6.5-inch
|
R-51M features a 1" Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1660Hz. On the other hand, the RTi A3 features a 1" silk polymer composite Dome Tweeter and 1 x 6.5" Polymer composite Woofer with a Crossover frequency at 2800Hz.
Frequency Response
R-51M has a frequency range of 62-21k Hz whereas RTi A3 has a frequency range of 50-26k Hz. With a minimum frequency of 50Hz, the RTi A3 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
R-51M and RTi A3 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. R-51M sensitivity is rated at 93 dB and the RTi A3's is at 89 dB. This 4 dB difference makes the Klipsch R-51M a more sensitive speaker compared to Polk RTi A3, 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.
R-51M can handle a max power of 150 watts RMS from the amp the whereas R-51M has a max power handling value of 85 watts RMS , 65 watts less than the RTi A3.
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.
Input Type and Bi-Amping / Bi-Wiring
RTi A3 features Pair of Dual 5-way Binding Posts - Gold-Plated posts which make bi-amping or bi-wiring possible. R-51M has a Single Gold Plated Binding Posts - 5-way which doesn't feature bi-amping/bi-wiring.
Klipsch R-51M's Single Gold Plated Binding Posts - 5-way terminals
Cabinet Type and Port Position
R-51M has a rear firing port whereas RTi A3 has a back and front firing ports.
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-51M's and Polk RTi A3's external dimensions. Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm ( 13.3 x 7.0 x 8.4inch) whereas Polk RTi A3 has external dimensions of 374.7 x 214.4 x 355.6mm ( 14.7 x 8.4 x 14.0inch) .
Polk RTi A3 is clearly the larger of the two speakers. Its body is 36.4mm wider, 36.7mm taller and 140.6mm deeper than Klipsch R-51M.
Below you can see the front view size comparison of Klipsch R-51M and Polk RTi A3 in scale.
Comparison image of Klipsch R-51M and Polk RTi A3 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 Klipsch R-51M is approximately 382.7cm2 / 59.3inch2 and base area of the Polk RTi A3 is approximately 762.4cm2 / 118.2inch2. The R-51M requires 50% less surface area than the RTi A3 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 Klipsch R-51M and Polk RTi A3 on a Media Console