Polk Audio Reserve R400 is a 2-way Passive Bass Reflex Center Channel speaker by Polk Audio. It was released in March 2021. Center channel speaker is an important component of a home theater system set-up as it delivers the listener significant part of the on-screen dialogue from your television. It features a 1" Pinnacle Ring Radiator Tweeter and 2 x 6.5" Polypropylene Turbine Cone Woofer. The speaker has a frequency range of 48-39K Hz and a sensitivity of 89 dB. Polk R400 has an MSRP of 649$.
Room Size Suitability
The size of the room where you plan to use the Polk R400 is a crucial factor in your decision. We have assessed its suitability for various room sizes based on its dimensions and maximum power output:
| Listening Environment* |
Suitability |
| Near-field | Poor |
| Small Room | Average |
| Mid-size Room | Good |
| Large Room | Average |
| Very Large Room | 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.)
Polk Audio's Reserve Series of Loudspeakers
R400 is a member of Polk Audio's Reserve series of Passive speakers. The Reserve range is Polk Audio's high-value step-up line, with Pinnacle tweeter and Power Port technology from the flagship Legend series. Below you can see the main specs of these speakers.
See all 10 Polk Audio Reserve models compared »
Polk Audio Reserve Series Speakers
**This post contains affiliate links, and we will be compensated if you make a purchase after clicking through our links. As an Amazon Associate I earn from qualifying purchases.
Frequency Response of the Polk R400 Speaker
Polk R400 has a Frequency response range of 48-39K Hz at ±3dB and Power Range of 20-200 watts.
Here we have a comparison of how R400's Low frequency value compares with the average, max and min Low frequency values in its class.
Low Frequency
Center Channel Speakers
Crossover frequency of the Polk R400?
The crossover frequency of the R400 is set to 2500Hz. This is the threshold frequency where the higher frequency signals over this level are sent to the tweeter and the lower-frequency signals are sent to the woofer by the crossover component.
Impedance and Sensitivity
Polk R400's nominal impedance level is
8 ohms but can go down to as low as
4.1 ohms, and has a sensitivity of
89 dB.
Sensitivity
Center Channel Speakers
8 Ohms is pretty much the standard nominal impedance amongst stereo speakers and amplifiers so Polk Audio Reserve R400 is not considered a difficult to drive speaker from nominal Impedance perspective.
Sensitivity
89dB of the Polk Audio Reserve R400 is an average sensitivity for stereo speaker so it is neither easy nor difficult to drive Sensitivity wise. Work out how loud the Polk R400 plays in your room →
Minimum Impedance of the Polk R400
Even though the nominal impedance of the R400 is 8 ohms, the minimum impedance level of this speaker according to Polk Audio is 4.1 ohms Polk Audio Reserve R400 so while choosing an amplifier, you should ideally check if the unit you are considering can provide this impedance level.
What amplifier does the Polk R400 need?
At normal listening levels in a medium room, about
9.5–150 W
per channel into 8 ohms.
Set your own conditions and we will rank every amplifier we cover.
Prefer to browse? Integrated amplifiers under $750, or every amplifier we cover.
Input Type
R400 features Binding post type connectors. Bi-amping and Bi-wiring are not possible.
Work out what gauge speaker cable this run needs →
Polk R400 Back View
Polk R400 External Dimensions and Weight
Polk R400 has external dimensions of (Height x Width x Depth) 7-13/16 x 24-5/16 x 14-5/8inch (199.0 x 618.0 x 372.0mm ).
Base Surface Area
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base area of Polk R400 is approximately 2299.0cm2 / 356.3inch2.
To get a better perspective on the real life size of Polk R400, let's compare it with a standard size Compact Disc which has a diameter of 4.7inch (120mm).
Polk R400 Speaker Size Compared to a Compact Disc
Find speakers that fit your shelf or alcove →
WeightThe Polk R400 weighs 14.91kg / 32.8lbs per piece. Here is a comparison of how R400's weight compares with the average, max and min weights in its class.
Weight
All Center Channel Speakers
Weight
Center Channel Speakers under $750
Cabinet type and Materials
Polk R400 has a
Bass Reflex type cabinet. Bass Reflex type loudspeakers (aka Ported, Vented or Reflex Port) have enclosures that uses a port, hole or vent cut into the cabinet. Ported designs are generally more efficient than the Sealed designs.
Speaker Feet
Polk R400 comes with Rubber Pads which you can use to secure your loudspeaker on the surface that you are putting on.
It is always recommended to use some kind of feet under all types of speakers. Besides limiting the movement of the speakers, it also compensates for non-flat surfaces and limits the contact surface area of the speaker. Rubber based feet also help isolating the vibrations within certain frequency ranges.
Port Position
Polk R400 is a rear-firing port speaker so you have to make sure you leave enough space between the back of the speaker and wall or bookshelf so that it has room to breathe.
Polk R400 dual Port
Available colors
Polk R400 is available in Black and Walnut.
Does the Polk R400 come with a Grille?
R400 comes with magnetic grilles. The purpose of the grille is to protect the delicate driver elements from external impacts while still allowing the sound to pass as clearly as possible. Since the included grille of the R400 is magnetic type, it is very easy to put it on and off.
Polk R400 with Grille
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
Recommended Accessories
Here is a list of accessories that we think you may need for the Polk Audio Reserve R400.
User's Manual
For more information about how to setup, use and maintain the Polk Audio Reserve R400, use the direct link below to download the official manual document:
Download User Manual for Polk R400
Official Brochure
Here is a link to download the official brochure for the Polk Audio Reserve R400 speaker:
Official Brochure for Polk R400
Official Product Page
Official manufacturer's product page for the Polk Audio Reserve R400 speaker can be found below:
Official Product Page for Polk R400
Warranty
5 Years of parts warranty and 5 Years of labor warranty is generally provided by the manufacturer.