Polk Audio Signature S15 is a 2-way Passive Bass Reflex Bookshelf speaker by Polk Audio. It features a 1" Dome Tweeter and 1 x 5.25" Mica-reinforced polypropylene Woofer. The speaker has a frequency range of 50-40k Hz and a sensitivity of 88 dB. Polk S15 has an MSRP of 259$ per pair but can often be found around 199$ per pair.
Room Size Suitability
The size of the room where you plan to use the Polk S15 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 | Average |
| Small Room | Good |
| Mid-size Room | Average |
| Large Room | Poor |
| Very Large Room | Bad |
(* 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 S15 with ES15. Follow the link to read our in-depth comparison of these speakers:
Compare Polk S15 vs Polk ES15
Polk Audio's Signature S Series of Loudspeakers
S15 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 S15 Speaker
Polk S15 has a Frequency response range of 50-40k Hz at ±3dB and Power Range of 20-100 watts. With a minimum frequency of 50 Hz, S15 delivers moderate bass depth so depending on your use case, you might want to consider adding a subwoofer to your system.
To focus on the subwoofers that are in a similar price range with Polk S15, check out the Powered Subwoofers under $300. Alternatively, find the Full list of Powered Subwoofers regardless of the price.
Here we have a comparison of how S15'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 S15?
The Crossover frequency of the S15 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 S15'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 S15 is not considered a difficult to drive speaker from nominal Impedance perspective.
Sensitivity
88dB of the Polk Audio Signature S15 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 S15:
Input Type
S15 features Pair of Binding Posts - Gold Plated type connectors. Bi-amping and Bi-wiring are not possible.
Polk S15 External Dimensions and Weight
Polk S15 has external dimensions of (Height x Width x Depth) 12.0 x 7.4 x 10.2inch (304.8 x 190.0 x 260.4mm ).
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 S15 is approximately 494.8cm2 / 76.7inch2.
WeightThe Polk S15 weighs 5.90kg / 13lbs per piece. Here is a comparison of how S15's weight compares with the average, max and min weights in its class.
Weight
All Bookshelf Speakers
Weight
Bookshelf Speakers under $300
Cabinet type and Materials
Polk S15 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 S15 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 S15 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 S15 is available in Black, Walnut and Brown Walnut.
Wall Mounting
S15 has Keyhole mounting bracket that makes it possible to mount on walls and similar surfaces easily.
Does the Polk S15 come with a Grille?
S15 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 S15?
Here are the items that are included inside the box of S15:
2 Bookshelf loudspeakers2 Grille (attached)8 Self-adhesive rubber feetWall-mount templateOwners ManualOnline Product Registration
Recommended Accessories
Here is a list of accessories that we think you may need for the Polk Audio Signature S15.
- 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 S15, use the direct link below to download the official manual document:
Download User Manual for Polk S15
Official Brochure
Here is a link to download the official brochure for the Polk Audio Signature S15 speaker:
Official Brochure for Polk S15
Official Product Page
Official manufacturer's product page for the Polk Audio Signature S15 speaker can be found below:
Official Product Page for Polk S15
Warranty
5 Years of parts warranty and 5 Years of labor warranty is generally provided by the manufacturer.