In this review, we will be comparing Contour 20 Black Edition and R-51M, two Passive Bookshelf speakers from Dynaudio and Klipsch.
Let's have a brief look at the main features
of Dynaudio Contour 20 Black Edition and Klipsch R-51M first before getting into our more
detailed comparison.
| Key Specs | Dynaudio Contour 20 Black Edition | Klipsch R-51M |
|---|
| Brand | Dynaudio
Denmark · founded 1977 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1.1" Soft-Dome | 1" Tractrix Horn |
|---|
| Woofer | 7" MSP | 5.25" Copper-spun IMG |
|---|
| Frequency response | 50-23k Hz | 62-21k Hz |
|---|
| Sensitivity | 86 dB | 93 dB |
|---|
| Impedance | 4 ohms | 8 ohms |
|---|
| Power range | — | Up to 85 watts |
|---|
| Weight | 14.60kg / 32.1lbs | 5.00kg / 11lbs |
|---|
| Dimensions (H x W x D) | 17-5/16" x 8-7/16" x 15-3/4"
440.0 x 215.0 x 400.0mm | 13.3" x 7.0" x 8.4"
338.0 x 178.0 x 215.0mm |
|---|
What size room are the Dynaudio Contour 20 Black Edition 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* |
Dynaudio Contour 20 Black Edition |
Klipsch R-51M |
| Near-field |
Good |
Average |
| Small Room |
Good |
Good |
| Mid-size Room |
Average |
Average |
| Large Room |
Poor |
Poor |
| Very Large Room |
No way |
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 Contour 20 Black Edition and R-51M are 2-way speakers.
Dynaudio Contour 20 Black EditionKlipsch 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 |
Dynaudio Contour 20 Black Edition |
Klipsch R-51M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1.1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 7-inch
|
1 x 5.25-inch
|
Contour 20 Black Edition features a 1.1" Esotar 3 Soft-Dome Tweeter and 1 x 7" MSP Woofer with a Crossover frequency at 3600Hz. 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
Contour 20 Black Edition has a frequency range of 50-23k Hz whereas R-51M has a frequency range of 62-21k Hz. With a minimum frequency of 50Hz, the Contour 20 Black Edition can go significantly deeper on the low side and provide stronger bass compared to 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
Contour 20 Black Edition is a 4 ohms speaker compared to the R-51M which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the Contour 20 Black Edition can provide this impedance level.
These two speakers also have different sensitivity levels. Contour 20 Black Edition sensitivity is rated at 86 dB and the R-51M's is rated at 93 dB. This 7 dB difference makes the Klipsch R-51M a more sensitive speaker compared to Dynaudio Contour 20 Black Edition, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf Speakers
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.
Dynaudio Contour 20 Black Edition
Input Type and Bi-Amping / Bi-Wiring
Contour 20 Black Edition 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.
Klipsch R-51M's Single Gold Plated Binding Posts - 5-way terminals
Cabinet Type and Port Position
Both Contour 20 Black Edition 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 Dynaudio Contour 20 Black Edition's and Klipsch R-51M's external dimensions. Dynaudio Contour 20 Black Edition has external dimensions of 440.0 x 215.0 x 400.0mm (17-5/16 x 8-7/16 x 15-3/4inch) whereas Klipsch R-51M has external dimensions of 338.0 x 178.0 x 215.0mm (13.3 x 7.0 x 8.4inch).
Dynaudio Contour 20 Black Edition is clearly the larger of the two speakers. Its body is 37mm wider, 102mm taller and 185mm deeper than Klipsch R-51M.
Size, drawn to scale
Both speakers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same surface and pushed back to the same wall, so the deeper one visibly sticks out further.
Dynaudio Contour 20 Black Edition needs about 125% more floor or shelf area. Dynaudio Contour 20 Black Edition is 185mm deeper, so it stands that much further out from the wall. Dynaudio Contour 20 Black Edition is 102mm taller.
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 Dynaudio Contour 20 Black Edition is approximately 860.0cm2 / 133.3inch2 and base area of the Klipsch R-51M is approximately 382.7cm2 / 59.3inch2. The Contour 20 Black Edition requires 125% more surface area than the R-51M 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 Dynaudio Contour 20 Black Edition weighs 14.60kg / 32.1lbs and the Klipsch R-51M weighs 5.00kg / 11lbs. This makes the Contour 20 Black Edition 192% heavier than the R-51M.
Here is a comparison of how Contour 20 Black Edition and R-51M's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
Dynaudio Contour 20 Black Edition
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 |
180 watts
vs
85 watts
|
Handle more power from your amplifier |
 Woofer Size |
7 inches
vs
5.25 inches
|
Larger woofer |
|
Low Frequency Response |
50 Hz
vs
62 Hz
|
Generates deeper bass |
 High Frequency Response |
23k Hz
vs
21k Hz
|
Generates higher frequency |
 Sensitivity |
93 dB
vs
86 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Height |
338mm
vs
440mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
382cm2
vs
860cm2
|
Takes less floor space |
| General |
Dynaudio Contour 20 Black Edition |
Klipsch Reference R-51M |
| Brand |
Dynaudio |
Klipsch |
| Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
| Sensitivity |
86 dB |
93 dB |
| Impedance |
4 ohms |
8 ohms |
| Frequency Response |
50-23k Hz |
62-21k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
7" |
5.25" |
| Woofer Composition |
MSP |
Copper-spun IMG |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1.1" |
1" |
| Tweeter Type |
Soft-Dome |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
3600Hz |
1660Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
440.0mm (17.3") |
338.0mm (13.3") |
| Width |
215.0mm (8.5") |
178.0mm (7") |
| Depth |
400.0mm (15.7") |
215.0mm (8.5") |
| Weight |
14.60kg (32.1lbs) |
5.00kg (11lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF/Wood-grain vinyl |
| Available Colors |
n/a |
Black |
| Mounting Bracket |
|
No |
| Recommended Stand Height |
n/a |
24-28" |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
No |
Other |
|
|
| Parts Warranty |
|
5 Years |
| Labor Warranty |
|
5 Years |
A generation apart: Dynaudio Contour 20 Black Edition is the newer design, against a 2018 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | A | Dynaudio Contour 20 Black Edition digs deeper - 50Hz against 62Hz. |
| Amplifier needs | B | Klipsch R-51M is more sensitive (93dB vs 86dB), so it goes louder on the same amplifier. |
| Amplifier match | B | Klipsch R-51M is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | A | Dynaudio Contour 20 Black Edition takes more power (180W vs 85W) - more in hand in a big room. |
| Size | depends | Klipsch R-51M is easier to place; Dynaudio Contour 20 Black Edition is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Klipsch R-51M sits in a wider range (5 models), so a matched surround system is easier later. |
A Dynaudio Contour 20 Black Edition 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?
Neither runs away with it - they trade advantages. Let the "depends" rows and your own room settle it. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 62Hz anyway, so judge these on the other rows instead. Match it to your room: we rate Dynaudio Contour 20 Black Edition the better fit for near-field listening; elsewhere the two are rated the same.
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.