Polk Audio Signature S20 is a 2-way Passive Bass Reflex Bookshelf speaker by Polk Audio. It features a 1" Soft-Dome Tweeter and 1 x 6.5" Mica-reinforced polypropylene Woofer. The speaker has a frequency range of 39-40k Hz and a sensitivity of 88 dB.
Room Size Suitability
The size of the room where you plan to use the Polk S20 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 later replaced S20 with ES20. Follow the link to read our in-depth comparison of these speakers:
Compare Polk S20 vs Polk ES20
Polk Audio's Signature S Series of Loudspeakers
S20 is a member of Polk Audio's Signature S series of Passive speakers. Below you can see the main specs of these speakers.
Polk Audio Signature S Series Speakers
Polk Audio Signature S Series Speakers
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Frequency Response of the Polk S20 Speaker
Polk S20 has a Frequency response range of 39-40k Hz at ±3dB and Power Range of 20-125 watts. With a minimum frequency of 39 Hz, S20 delivers deep bass that will likely satisfy most listeners, especially those who enjoy music. However, movie enthusiasts and music fans who prefer a full range of sound may still benefit from adding a subwoofer.
Visit our Powered Subwoofers section to find out more about the available subwoofer options.
Here we have a comparison of how S20's Low and High frequency values compare with the average, max and min Low and High frequency values in its class.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf Speakers
Crossover frequency of the Polk S20?
The Crossover frequency of the S20 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 S20's nominal impedance level is
8 ohms and has a sensitivity of
88 dB.
Sensitivity
Bookshelf Speakers
8 Ohms is pretty much the standard nominal impedance amongst stereo speakers and amplifiers so Polk Audio Signature S20 is not considered a difficult to drive speaker from nominal Impedance perspective.
Sensitivity
88dB of the Polk Audio Signature S20 is an average sensitivity for stereo speaker so it is neither easy nor difficult to drive Sensitivity wise.
Check the amplifiers that are in a similar price range to the Polk S20:
Input Type
S20 features 5-way post type connectors. Bi-amping and Bi-wiring are not possible.
Polk S20 External Dimensions and Weight
Polk S20 has external dimensions of (Height x Width x Depth) 14.8 x 8.5 x 13.7inch (376.0 x 216.0 x 350.0mm ).
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 S20 is approximately 756.0cm2 / 117.2inch2.
To get a better perspective on the real life size of Polk S20, let's compare it with a standard size Compact Disc which has a diameter of 4.7inch (120mm).
Polk S20 Speaker Size Compared to a Compact Disc
Here we place the Polk S20 virtually next to a standard width amplifier and turntable on a BDI Octave Media Cabinet to get a better idea about the size.
Polk S20 Speaker next to an amplifier and turntable
WeightThe Polk S20 weighs 7.73kg / 17lbs per piece. Here is a comparison of how S20's weight compares with the average, max and min weights in its class.
Weight
All Bookshelf Speakers
Cabinet type and Materials
Polk S20 has a
Bass Reflex type cabinet and a Meddite MDF finish. 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 S20 comes with
8 Self-adhesive rubber feet 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 S20 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.
Available colors
Polk S20 is available in Black, Walnut and Brown Walnut.
Wall Mounting
S20 doesn't sport any built-in mounting bracket, so you need an external structure to mount it on walls.
Does the Polk S20 come with a Grille?
S20 comes with 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.
What's in the Box of Polk S20?
Here are the items that are included inside the box of S20:
2 Bookshelf loudspeakers2 Grilles (attached)8 Self-adhesive rubber feetOwners ManualOnline Product Registration
Recommended Accessories
Here is a list of accessories that we think you may need for the Polk Audio Signature S20.
- Speaker Cable and Connectors
- 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.
- Speaker Stands: Stands bring your bookshelf speakers to ideal height (rule of thumb is to have the tweeter level with your ear in your listening position), helps stability and acoustical isolation.
User's Manual
For more information about how to setup, use and maintain the Polk Audio Signature S20, use the direct link below to download the official manual document:
Download User Manual for Polk S20
Official Brochure
Here is a link to download the official brochure for the Polk Audio Signature S20 speaker:
Official Brochure for Polk S20
Official Product Page
Official manufacturer's product page for the Polk Audio Signature S20 speaker can be found below:
Official Product Page for Polk S20
Warranty
5 Years of parts warranty and 5 Years of labor warranty is generally provided by the manufacturer.