In this review, we will be comparing R400 and Demand D5C, two Passive Center Channel speakers from Polk Audio and Definitive Technology.
Let's have a brief look at the main features
of Polk R400 and Definitive D5C first before getting into our more
detailed comparison.
| Key Specs | Polk R400 | Definitive D5C |
|---|
| Brand | Polk Audio
United States · founded 1972 | Definitive Technology
United States · founded 1990 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" Pinnacle Ring Radiator | 1" dome |
|---|
| Woofer | 2 x 6.5" Polypropylene Turbine Cone | 2 x 5.25" BDSS |
|---|
| Frequency response | 48-39K Hz | 42-22k Hz |
|---|
| Sensitivity | 89 dB | 85.5 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 20-200 watts | 30-200 watts |
|---|
| Weight | 14.91kg / 32.8lbs | 10.91kg / 24lbs |
|---|
| Dimensions (H x W x D) | 7-13/16" x 24-5/16" x 14-5/8"
199.0 x 618.0 x 372.0mm | 6-5/8" x 19-1/16" x 11-3/8"
169.0 x 485.0 x 289.0mm |
|---|
What size room are the Polk R400 and Definitive D5C 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* |
Polk R400 |
Definitive D5C |
| 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.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both R400 and Demand D5C are 2-way speakers.
Polk R400Definitive D5C
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Polk R400 |
Definitive D5C |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 6.5-inch
|
2 x 5.25-inch
|
R400 features a 1" Pinnacle Ring Radiator Tweeter and 2 x 6.5" Polypropylene Turbine Cone Woofer with a Crossover frequency at 2500Hz. On the other hand, the Demand D5C features a 1" aluminum dome Tweeter and 2 x 5.25" BDSS Woofer.
Frequency Response
R400 has a frequency range of 48-39K Hz whereas Demand D5C has a frequency range of 42-22k Hz. With a minimum frequency of 42Hz, the Demand D5C can go significantly deeper on the low side and provide stronger bass compared to the R400's min frequency of 48Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Center Channel class in our database.
Low Frequency
Center Channel 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
R400 and Demand D5C have the same Impedance of 8 ohms but where they differ is the sensitivity levels. R400 sensitivity is rated at 89 dB and the Demand D5C's is at 85.5 dB. This 3 dB difference makes the Polk R400 a more sensitive speaker compared to Definitive D5C, hence will play louder with the same amount of watts.
Sensitivity
Center Channel 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.
Both handle the same maximum of 200 watts RMS, though R400 is rated 20-200 watts and Demand D5C 30-200 watts.
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
R400 features 5-Way post type posts and Demand D5C has a 5-Way post type posts. None of these speakers feature bi-amping/bi-wiring.
Polk R400's Binding post terminals
Definitive D5C's 5-Way post terminals
Polk R400 dual Port
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 Polk R400's and Definitive D5C's external dimensions. 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) whereas Definitive D5C has external dimensions of 169.0 x 485.0 x 289.0mm (6-5/8 x 19-1/16 x 11-3/8inch).
Polk R400 is clearly the larger of the two speakers. Its body is 133mm wider, 30mm taller and 83mm deeper than Definitive D5C.
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 Polk R400 is approximately 2299.0cm2 / 356.3inch2 and base area of the Definitive D5C is approximately 1401.7cm2 / 217.3inch2. The R400 requires 64% more surface area than the Demand D5C 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 Polk R400 weighs 14.91kg / 32.8lbs and the Definitive D5C weighs 10.91kg / 24lbs. This makes the R400 37% heavier than the Demand D5C.
Here is a comparison of how R400 and Demand D5C's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
What's in the Box of Polk R400?
Here are the items that are included inside the box of R400:
- Center-channel loudspeaker
- Grille
- Owners Manual
- Online Registration
What's in the Box of Definitive D5C?
Here are the items that come with the Demand D5C:
- Center-channel loudspeaker
- Grille
- Cleaning cloth
- Owners Manual
 Sensitivity |
89 dB
vs
86 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
 High Frequency Response |
39k Hz
vs
22k Hz
|
Generates higher frequency |
 Price per pair* |
649USD
vs
799USD
|
costs less (*prices may change depending on the seller, location and time) |
|
Low Frequency Response |
42 Hz
vs
48 Hz
|
Generates deeper bass |
 Height |
169mm
vs
199mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1401cm2
vs
2299cm2
|
Takes less floor space |
| General |
Polk Audio Reserve R400 |
Definitive Technology Demand D5C |
| Brand |
Polk Audio |
Definitive Technology |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
20-200 watts |
30-200 watts |
| Sensitivity |
89 dB |
85.5 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
4.1 ohms |
n/a |
| Frequency Response |
48-39K Hz |
42-22k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
5.25" |
| Woofer Composition |
Polypropylene Turbine Cone |
BDSS |
| Woofer Surround Material |
Rubber |
n/a |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Pinnacle Ring Radiator |
dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2500Hz |
n/a |
| Firing Direction |
rear |
n/a |
Physical Specs |
|
|
| Height |
199.0mm (7.8") |
169.0mm (6.7") |
| Width |
618.0mm (24.3") |
485.0mm (19.1") |
| Depth |
372.0mm (14.6") |
289.0mm (11.4") |
| Weight |
14.91kg (32.8lbs) |
10.91kg (24lbs) |
| Enclosure |
Bass Reflex |
Acoustic Suspension |
| Available Colors |
Black, Walnut |
Gloss White |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
n/a |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
No single best speaker here - they are built to different priorities, and the right one depends on your room, your amplifier and what you listen to.
| Area | Better | Why |
|---|
| Bass | B | Definitive D5C digs deeper - 42Hz against 48Hz. A subwoofer would even that out. |
| Amplifier needs | A | Polk R400 is more sensitive (89dB vs 86dB), so it goes louder on the same amplifier. |
| Headroom | evenly matched | Similar power handling (200W vs 200W). |
| Size | depends | Definitive D5C is easier to place; Polk R400 is bigger, which usually goes with fuller bass. Your room decides. |
| Cabinet | depends | Ported vs Sealed. Sealed is tighter and happier near a wall; ported digs lower but wants space behind it. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Polk R400 sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | A | Polk R400 is cheaper - $649 against $799, about 19% less. |
A Polk R400 B Definitive D5C
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 48Hz anyway, which makes the cheaper Polk R400 much easier to justify. In a large or open-plan room, Polk R400 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Definitive D5C 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.