In this review, we will be comparing M106 and R-51M, two Passive Bookshelf speakers from Revel and Klipsch.
Let's have a brief look at the main features
of Revel M106 and Klipsch R-51M first before getting into our more
detailed comparison.
| Key Specs | Revel M106 | Klipsch R-51M |
|---|
| Brand | Revel
United States · founded 1996 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Hard-Dome with Acoustic Lens Waveguide | 1" Tractrix Horn |
|---|
| Woofer | 6.5" Aluminum | 5.25" Copper-spun IMG |
|---|
| Frequency response | 59Hz- 20kHz | 62-21k Hz |
|---|
| Sensitivity | 87 dB | 93 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 50-150 watts | Up to 85 watts |
|---|
| Weight | 8.41kg / 18.5lbs | 5.00kg / 11lbs |
|---|
| Dimensions (H x W x D) | 15-1/16" x 8-1/4" x 11"
383.0 x 210.0 x 280.0mm | 13.3" x 7.0" x 8.4"
338.0 x 178.0 x 215.0mm |
|---|
What size room are the Revel M106 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* |
Revel M106 |
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.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both M106 and R-51M are 2-way speakers.
Revel M106Klipsch R-51M
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Revel M106 |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 6.5-inch
|
1 x 5.25-inch
|
M106 features a 1" aluminum Hard-Dome with Acoustic Lens Waveguide Tweeter and 1 x 6.5" Aluminum Woofer with a Crossover frequency at 2300Hz. 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
M106 has a frequency range of 59Hz- 20kHz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 59Hz, the M106 can go slightly deeper then the R-51M's min frequency of 62Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
M106 and R-51M have the same Impedance of 8 ohms but where they differ is the sensitivity levels. M106 sensitivity is rated at 87 dB and the R-51M's is at 93 dB. This 6 dB difference makes the Klipsch R-51M a more sensitive speaker compared to Revel M106, 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. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
M106 can handle a max power of 150 watts RMS, whereas R-51M has a max power handling value of 85 watts RMS, 65 watts less than the M106.
Note that higher power handling does not make a speaker louder: that depends mainly on
sensitivity and impedance. The calculator below shows how loud each of these actually plays
on a real amplifier.
Which plays louder on your amplifier?
Starting with a popular amplifier - change it to the one you own, or any you are
considering, and watch both numbers move.
Input Type and Bi-Amping / Bi-Wiring
M106 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.
Revel M106's Binding post terminals
Klipsch R-51M's Single Gold Plated Binding Posts - 5-way terminals
Cabinet Type and Port Position
Both M106 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
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Revel M106's and Klipsch R-51M's external dimensions. Revel M106 has external dimensions of 383.0 x 210.0 x 280.0mm (15-1/16 x 8-1/4 x 11inch) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm (13.3 x 7.0 x 8.4inch).
Revel M106 is clearly the larger of the two speakers. Its body is 32mm wider, 45mm taller and 65mm deeper than Klipsch R-51M.
Below you can see the front view size comparison of Revel M106 and Klipsch R-51M in scale.
Comparison image of Revel M106 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 Revel M106 is approximately 588.0cm2 / 91.1inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The M106 requires 54% more surface area than the R-51M which gives it a small disadvantage on placement in tight spaces.
Here is 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 Revel M106 and Klipsch R-51M on a Media Console
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 Revel M106 weighs 8.41kg / 18.5lbs and the Klipsch R-51M weighs 5.00kg / 11lbs. This makes the M106 68% heavier than the R-51M.
Here is a comparison of how M106 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 Revel M106?
Here are the items that are included inside the box of M106:
- Bookshelf loudspeaker
- Grille
- Foam port plug
- Owners Manual
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 |
150 watts
vs
85 watts
|
Handle more power from your amplifier |
 Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
|
Low Frequency Response |
59 Hz
vs
62 Hz
|
Generates deeper bass |
 Sensitivity |
93 dB
vs
87 dB
|
Play louder with same amount of amplification power |
 High Frequency Response |
21k Hz
vs
20k Hz
|
Generates higher frequency |
 Height |
338mm
vs
383mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
382cm2
vs
588cm2
|
Takes less floor space |
 Price per pair* |
359USD
vs
2200USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Revel Performa3 M106 |
Klipsch Reference R-51M |
| Brand |
Revel |
Klipsch |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Power Range |
50-150 watts |
Up to 85 watts |
| Sensitivity |
87 dB |
93 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
59Hz- 20kHz |
62-21k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
6.5" |
5.25" |
| Woofer Composition |
Aluminum |
Copper-spun IMG |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Hard-Dome with Acoustic Lens Waveguide |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2300Hz |
1660Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
383.0mm (15.1") |
338.0mm (13.3") |
| Width |
210.0mm (8.3") |
178.0mm (7") |
| Depth |
280.0mm (11") |
215.0mm (8.5") |
| Weight |
8.41kg (18.5lbs) |
5.00kg (11lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
Wood/Lacquer |
MDF/Wood-grain vinyl |
| Available Colors |
Gloss Walnut,Piano Black |
Black |
| Mounting Bracket |
No |
No |
| Recommended Stand Height |
24-25" |
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 |
These sit in different price classes - Revel M106 costs roughly 6.1x what Klipsch R-51M does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | A | Revel M106 digs deeper - 59Hz against 62Hz. A subwoofer would even that out. |
| Amplifier needs | B | Klipsch R-51M is more sensitive (93dB vs 87dB), so it goes louder on the same amplifier. |
| Headroom | A | Revel M106 takes more power (150W vs 85W) - more in hand in a big room. |
| Size | depends | Klipsch R-51M is easier to place; Revel M106 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Revel M106 sits in a wider range (8 models), so a matched surround system is easier later. |
| Price | B | Klipsch R-51M is cheaper - $359 against $2,200, about 84% less; arguably a different class. |
A Revel M106 B Klipsch R-51M
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Revel M106 is ahead, but only on 1 of the measured areas, and it costs about 6.1x the price. That is a lot of money for a narrow margin on paper - Klipsch R-51M looks like the sensible buy unless something else about the Revel M106 appeals to you. Match it to your room: we rate Revel M106 the better fit for a mid-size room and a large room, and Klipsch R-51M for near-field listening and a small room. In a large or open-plan room, Revel M106 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Klipsch R-51M is the easier speaker to get right.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.