In this review, we will be comparing Dymension DM20 and R400, two Passive Center Channel speakers from Definitive Technology and Polk Audio. Let's have a brief look at the main features
of Definitive Dymension DM20 and Polk R400 first before getting into our more
detailed comparison.
What size room are the Definitive Dymension DM20 and Polk R400 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 Definitive Dymension DM20 and Polk R400 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 Dymension DM20 and R400 are 2-way speakers.
| Driver |
Definitive Dymension DM20 |
Polk R400 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
4 x 4.5-inch
|
2 x 6.5-inch
|
Dymension DM20 features a 1" aluminum oxide Hard-Dome Tweeter and 4 x 4.5" Polypropelene Woofer . On the other hand, the R400 features a 1" Pinnacle Ring Radiator Tweeter and 2 x 6.5" Polypropylene Turbine Cone Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Dymension DM20 has a frequency range of 91-23 kHz whereas R400 has a frequency range of 48-39K Hz. With a minimum frequency of 48Hz, the R400 can go significantly deeper on the low side and provide stronger bass compared to the Dymension DM20's min frequency of 91Hz.
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 Center Channel class in our database.
Low Frequency
Center Channel Speakers
High Frequency
Center Channel Speakers
Definitive Dymension DM20
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
Dymension DM20 is a 4 ohms speaker compared to the R400 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 Dymension DM20 can provide this impedance level.
On the other hand, they have the same sensitivity of 89 dBdB.
Sensitivity
Center Channel 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.
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
Dymension DM20 features Binding post type posts and R400 has a Binding post type posts. None of these speakers feature bi-amping/bi-wiring.
Definitive Dymension DM20's Binding post terminals
Polk R400's Binding post terminals
Polk R400 dual Port
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 Definitive Dymension DM20's and Polk R400's external dimensions. Definitive Dymension DM20 has external dimensions of 134 x 775 x 166 mm ( 5.3 x 30.5 x 6.5 in) whereas Polk R400 has external dimensions of 199.0 x 618.0 x 372.0mm ( 7-13/16 x 24-5/16 x 14-5/8inch) .
Definitive Dymension DM20 is 65mm shorter and 206mm less deeper than Polk R400 but it is also 157mm wider.
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 Definitive Dymension DM20 is approximately 1286.5cm2 / 199.4inch2 and base area of the Polk R400 is approximately 2299.0cm2 / 356.3inch2. The Dymension DM20 requires 44% less surface area than the R400 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 Definitive Dymension DM20 weighs 10.00kg / 22lbs and the Polk R400 weighs 14.91kg / 32.8lbs. This makes the R400 49% heavier than the Dymension DM20.
Here is a comparison of how Dymension DM20 and R400's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
Definitive Dymension DM20
What's in the Box of Polk R400?
Here are the items that come with the R400:
Center-channel loudspeakerGrilleOwners ManualOnline Registration
 Number of Woofers |
4
vs
2
|
More woofers |
 Mounting Bracket |
Yes
vs
No
|
Allows mounting on walls |
 Height |
134mm
vs
199mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1286cm2 (775x166mm)
vs
2299cm2 (618x372mm)
|
Takes less floor space |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
| Woofer Size |
6.5 inches
vs
4.5 inches
|
Larger woofer |
| Low Frequency Response |
48 Hz
vs
91 Hz
|
Generates deeper bass |
 High Frequency Response |
39k Hz
vs
23k Hz
|
Generates higher frequency |
 Price per pair* |
649USD
vs
799USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Definitive Technology Dymension DM20 |
Polk Audio Reserve R400 |
| Brand |
Definitive Technology |
Polk Audio |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
50-200 watts |
20-200 watts |
| Sensitivity |
89 dB |
89 dB |
| Impedance |
4 ohms |
8 ohms |
| Impedance |
n/a |
4.1 ohms |
| Frequency Response |
91-23 kHz |
48-39K Hz |
Drivers |
|
|
| Woofer Quantity |
4 |
2 |
| Woofer Size |
4.5" |
6.5" |
| Woofer Composition |
Polypropelene |
Polypropylene Turbine Cone |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Hard-Dome |
Pinnacle Ring Radiator |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
N/A" |
| Crossover Frequency |
n/a |
2500Hz |
| Firing Direction |
n/a |
rear |
Physical Specs |
|
|
| Height |
134.0mm (5.3") |
199.0mm (7.8") |
| Width |
775.0mm (30.5") |
618.0mm (24.3") |
| Depth |
166.0mm (6.5") |
372.0mm (14.6") |
| Weight |
10.00kg (22lbs) |
14.91kg (32.8lbs) |
| Enclosure |
Acoustic Suspension |
Bass Reflex |
| Available Colors |
Black |
Black, Walnut |
| 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 |