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Definitive Dymension DM20 vs Polk R400 Comparison

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Definitive Dymension DM20

Passive Center Channel | 91-23 kHz

Definitive Technology Dymension DM20
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Polk R400

Passive Center Channel | 48-39K Hz

Polk Audio Reserve R400
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Definitive Dymension DM20 Definitive Dymension...
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Polk R400 Polk R400
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Definitive Dymension...
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Polk R400
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Definitive Dymension DM20 vs Polk R400 Speaker Comparison

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.

Definitive Dymension DM20 Key Specs

  • 2-way Design
  • 1" Hard-Dome Tweeter
  • 4 x 4.5" Polypropelene Woofer
  • 91-23 kHz Frequency Response
  • 89 dB Sensitivity
  • Impedance: 4ohms
  • Power Range:50-200watts
  • Weight:10.00kg
  • Dimensions (H x W x D): 134.0" x 30.5" x 6.5"( 134 x 775 x 166 mm )

Polk R400 Key Specs

  • 2-way Design
  • 1" Pinnacle Ring Radiator Tweeter
  • 2 x 6.5" Polypropylene Turbine Cone Woofer
  • 48-39K Hz Frequency Response
  • 89 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:20-200watts
  • Weight:14.91kg
  • Dimensions (H x W x D): 199.0" x 24-5/16" x 14-5/8"( 199.0 x 618.0 x 372.0mm )

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:

Listening Environment* Definitive Dymension DM20 Polk R400
Near-field Poor Poor
Small Room Average Average
Mid-size Room Good Good
Large Room Average Average
Very Large Room Poor 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 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.


**This post contains affiliate links, and I will be compensated if you make a purchase after clicking 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

Dymension DM20
R400
Min
Average
Max
High Frequency

Center Channel Speakers

Definitive Dymension DM20
Polk R400
Min
Average
Max

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

Dymension DM20
R400
Min
Average
Max

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 Terminals
Definitive Dymension DM20's Binding post terminals

Polk R400Binding post Terminals
Polk R400's Binding post terminals

Polk R400  Port
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
Polk R400
Min
Average
Max

What's in the Box of Polk R400?

Here are the items that come with the R400:
  • Center-channel loudspeaker
  • Grille
  • Owners Manual
  • Online Registration

  • Reasons to choose Definitive Technology Dymension DM20 over Polk Audio Reserve R400
    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 vs 2299cm2 Takes less floor space

    Reasons to choose Polk Audio Reserve R400 over Definitive Technology Dymension DM20

    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)
    Definitive Dymension DM20 vs Polk R400 Specs Table
    Detailed comparison of specifications
    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

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