SpeakerDecision
  • SPEAKERS by TYPE
    • Passive Bookshelf Speakers
    • Passive Floor-standing Speakers
    • Passive Center Channel Speakers
    • Passive In-wall Speakers
    • All Passive Speakers
    • Powered Subwoofers
    • Powered Stereo Speakers
  • AMPLIFIERS
  • SMART FIND
  1. Home
  2. Polk-Audio Speakers
  3. Passive Center Channel Speakers
Polk Audio R400 Review
Polk Audio Reserve R400

Main Features

  • 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:32.80 lbs / 14.91 kg
  • Dimensions(HxWxD): 7-13/16"x24-5/16"x14-5/8" / 199.0 x 618.0 x 372.0mm
CHECK PRICE

Compare To

x
Add a Speaker for comparison
Polk R400 Review
Polk R400 Polk R400
See at AMAZON

Polk Audio Reserve R400 is a 2-way Passive Bass Reflex Center Channel speaker by Polk Audio. 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-fieldPoor
Small RoomAverage
Mid-size RoomGood
Large RoomAverage
Very Large RoomPoor

(* 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. Below you can see the main specs of these speakers.

Polk Audio Reserve Series Speakers
Model Frequency SensitivityImpedance Woofer
Polk R700
Compare
38-38k Hz 88 dB8Ω 2 x 8"
Polk R500
Compare
49-36k Hz 87 dB8Ω 2 x 5.25"
Polk R600
Compare
43-38k Hz 87.5 dB8Ω 2 x 6.5"
Polk R200
Compare
51-38k Hz 86 dB8Ω 1 x 6.5"
Polk R400
48-39k Hz 89 dB8Ω 2 x 6.5"
Polk R100
Compare
58-39k Hz 86 dB8Ω 1 x 5.25"
Polk R300
Compare
65-38k Hz 86.5 dB8Ω 2 x 5.25"
Polk R200 50th AE
Compare
51-38k Hz 86 dB8Ω 1 x 6.5"


**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.

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 and High frequency values compare with the average, max and min Low and High frequency values in its class.

Low Frequency
Center Channel Speakers
Polk R400
Min
Average
Max
High Frequency
Center Channel Speakers
Polk R400
Min
Average
Max

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
Polk R400
Min
Average
Max

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.

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.

Check the amplifiers that are in a similar price range to the Polk R400:

  • Integrated Amps under 500 USD
  • Integrated Amps under 750 USD
  • Integrated Amps under 1000 USD
  • All Integrated Amplifiers

Input Type

R400 features Binding post type connectors. Bi-amping and Bi-wiring are not possible.
Polk R400 Back View
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.

Weight

The 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
Polk R400
Min
Average
Max
Weight
Center Channel Speakers under $750
Polk R400
Min
Average
Max

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  Port
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
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.

    • Speaker Cable and Connectors
      • Speaker Cables with Banana Plugs: If you know the lenght of the cable you need, this is the easier option to connect your speakers with your amp.
      • Speaker Cables without Connectors: If you are not sure about the lenght or need longer than standard cables with plugs, choose this option.
      • Banana Connectors and Plugs: If you chose the cables without connectors option or already have some cable around, pick the banana plugs separately.
    • Vibration Isolators: IsoAcoustics isolators more affordable options too.
    • Acoustic Panels and Treatments: Your room is as important as your stereo equipment so acoustic treatments goes a long way in improving the overall performance.

    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.

    Polk Audio Reserve R400 Alternatives in Passive Center Channel Speakers
    Model Type Sensitivity Impedance Frequency
    Polk L400
    Compare
    3-way 87.5 dB 4 ohms 55-38k Hz
    Polk R300
    Compare
    2-way 86.5 dB 8 ohms 65-38k Hz
    SVS Ultra Center
    Compare
    3-way 87 dB 8 ohms 45-32k Hz
    Polk ES30
    Compare
    2-way 89 dB 8 ohms 55-40k Hz
    Polk CSi A6
    Compare
    2-way 90 dB 8 ohms 55-26k Hz
    Klipsch RP-504C II
    Compare
    2-way 96 dB 8 ohms 50-25k Hz
    KEF Q650c
    Compare
    2-way 87 dB 8 ohms 64-28k Hz
    SVS Prime Center
    Compare
    3-way 86 dB 8 ohms 48-25k Hz
    Frequently Asked Questions about Polk Audio Reserve R400
    What is the External Dimensions of Polk Audio Reserve R400
    What is the Speaker Sensitivity of Polk Audio Reserve R400
    is the Polk Audio Reserve R400 an easy to drive speaker?

    Polk R400 Detailed Specifications

    General
    BrandPolk Audio
    Full Model NamePolk Audio Reserve R400
    Speaker Type2-way Center Channel
    Power Range20-200 watts
    Sensitivity89 dB
    Impedance8 ohms
    Frequency Response48-39K Hz
    DRIVERS
    Woofer Size6.5-inch
    Woofer CompositionPolypropylene Turbine Cone
    Woofer SurroundRubber
    Tweeter Size1-inch
    Tweeter TypePinnacle Ring Radiator
    Midrange SizeN/A-inch
    Crossover freq2500Hz
    Port Positionrear

    CONNECTIONS
    Connector TypeBinding post
    Biamp InputsNo
    Port Positionrear
    PHYSICAL SPECS
    Height199.0mm ( 7-13/16-inch)
    Width618.0mm ( 24-5/16-inch)
    Depth372.0mm ( 14-5/8-inch)
    Height199.0mm ( 7-13/16-inch)
    Weight14.91kg ( 32.80 lbs)
    EnclosureBass Reflex
    Available ColorsBlack, Walnut
    Mounting BracketNo
    GrilleYes
    Moisture ResistanceNo
    OTHER
    Handheld RemoteNo
    Parts Warranty5 Years
    Labor Warranty5 Years
    LATEST BLOG POSTS

    Klipsch La Scala AL6 and Klipschorn AK7 Speakers are Unveiled
    New Audiolab 6000A MkII with upgraded DAC and new HDMI ARC connection
    Q Acoustics 3000c Series Loudspeakers added to the database
    WiiM VibeLink Amp: A Game-Changer for Budget Hi-Fi in 2025
    KEF Meta and Reference Meta Floorstanding Speaker Size and Specs Comparison
    Triangle Borea Bookshelf and Floorstanding Speaker Size and Specs Comparison


    Latest Passive Center Channel Speakers
    Q Acoustics 3090Ci
    Q Acoustics 3090Ci
    2-way Center Channel | 89 dB | 6 ohms
    Q Acoustics 3090c
    Q Acoustics 3090c
    2-way Center Channel | 92 dB | 6 ohms
    ELAC Debut 3.0 DC63
    ELAC Debut 3.0 DC63
    2-way Center Channel | 87.5 dB | 6 ohms
    ELAC Debut 3.0 DC53
    ELAC Debut 3.0 DC53
    2-way Center Channel | 87.5 dB | 4 ohms
    Monitor Audio Gold C250 6G
    Monitor Audio Gold C250 6G
    3-way Center Channel | 87.5 dB | 4 ohms
    KEF Q6 Meta
    KEF Q6 Meta
    3-way Center Channel | 86 dB | 4 ohms
    JBL Stage 245C
    JBL Stage 245C
    2-way Center Channel | 91 dB | 6 ohms
    Elac Vela 2.0 VCC401.2-GB
    Elac Vela 2.0 VCC401.2-GB
    3-way Center Channel | 88.5 dB | 4 ohms
    Elac Solano 2.0 CC281.2-GB
    Elac Solano 2.0 CC281.2-GB
    3-way Center Channel | 87.5 dB | 4 ohms
    SVS Ultra Evolution Center
    SVS Ultra Evolution Center
    3-way Center Channel | 87 dB | 6 ohms


    Copyright © 2025 by SpeakerDecision
    About Privacy Contact US Camera Decision
    Compare List

      Add a speaker to the List