In this review, we will be comparing Sib Evo and R-51M, two Passive Bookshelf speakers from Focal and Klipsch. Let's have a brief look at the main features
of Focal Sib Evo and Klipsch R-51M first before getting into our more
detailed comparison.
What size room are the Focal Sib Evo 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:
In the following sections, we will get into more detail in order to better understand how the Focal Sib Evo 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 Sib Evo and R-51M are 2-way speakers.
| Driver |
Focal Sib Evo |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5-inch
|
1 x 5.25-inch
|
Sib Evo features a 1" Soft-Dome Tweeter and 1 x 5" Polyflex Woofer . 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
Sib Evo has a frequency range of 70-25k Hz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 62Hz, the R-51M can go significantly deeper on the low side and provide stronger bass compared to the Sib Evo's min frequency of 70Hz.
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
Sib Evo 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. Sib Evo sensitivity is rated at 90 dB and the R-51M's is rated at 93 dB. This 3 dB difference makes the Klipsch R-51M a more sensitive speaker compared to Focal Sib Evo, 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.
Sib Evo can handle a max power of 200 watts RMS from the amp the whereas R-51M has a max power handling value of 85 watts RMS, 115 watts less than the Sib Evo.
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
Sib Evo features Single Gold Plated Binding Posts - 5-way type posts and R-51M has a Single Gold Plated Binding Posts - 5-way type posts. None of these speakers feature bi-amping/bi-wiring.
Focal Sib Evo's Push button terminals
Klipsch R-51M's Single Gold Plated Binding Posts - 5-way terminals
Cabinet Type and Port Position
Both Sib Evo 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.
New
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 Focal Sib Evo's and Klipsch R-51M's external dimensions. Focal Sib Evo has external dimensions of 251.0 x 162.0 x 164.0mm ( 28-36inch x 6-3/8inch x 6-7/16inch ) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm ( 13.3 x 7.0 x 8.4inch) .
Klipsch R-51M is clearly the larger of the two speakers. Its body is 16mm wider, 87mm taller and 51mm deeper than Focal Sib Evo.
Below you can see the front view size comparison of Focal Sib Evo and Klipsch R-51M in scale.
Comparison image of Focal Sib Evo 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 Focal Sib Evo is approximately 265.7cm2 / 41.2inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The Sib Evo requires 31% less surface area than the R-51M 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 Focal Sib Evo weighs 1.80kg / 4lbs and the Klipsch R-51M weighs 5.00kg / 11lbs. This makes the R-51M 178% heavier than the Sib Evo.
Here is a comparison of how Sib Evo and R-51M's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Focal Sib Evo?
Here are the items that are included inside the box of Sib Evo:
2 Satellite loudspeakers (base attached)2 Wall-mount brackets6 Screws6 Wall-anchorsUser ManualThank You card
What's in the Box of Klipsch R-51M?
Here are the items that come with the R-51M:
2 Bookshelf loudspeakers 2 Grilles (installed) 8 Self-adhesive rubber feet Quick Setup Guide Important Safety Instructions Warranty Information
 Max Input Power |
200 watts
vs
85 watts
|
Handle more power from your amplifier |
 High Frequency Response |
25k Hz
vs
21k Hz
|
Generates higher frequency |
 Mounting Bracket |
Yes
vs
No
|
Allows mounting on walls |
 Height |
251mm
vs
338mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
265cm2 (162x164mm)
vs
382cm2 (178x215mm)
|
Takes less floor space |
 Sensitivity |
93 dB
vs
90 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Woofer Size |
5.25 inches
vs
5 inches
|
Larger woofer |
| Low Frequency Response |
62 Hz
vs
70 Hz
|
Generates deeper bass |
 Price per pair* |
359USD
vs
499USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Focal Sib Evo |
Klipsch Reference R-51M |
| Brand |
Focal |
Klipsch |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
25-200 watts |
Up to 85 watts |
| Sensitivity |
90 dB |
93 dB |
| Impedance |
6 ohms |
8 ohms |
| Frequency Response |
70-25k Hz |
62-21k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5" |
5.25" |
| Woofer Composition |
Polyflex |
Copper-spun IMG |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Soft-Dome |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
1660Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
251.0mm (9.9") |
338.0mm (13.3") |
| Width |
162.0mm (6.4") |
178.0mm (7") |
| Depth |
164.0mm (6.5") |
215.0mm (8.5") |
| Weight |
1.80kg (4lbs) |
5.00kg (11lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Lacquer |
MDF/Wood-grain vinyl |
| Available Colors |
Black |
Black |
| Mounting Bracket |
Yes |
No |
| Recommended Stand Height |
28-36" |
24-28" |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
No |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |