The American brand Polk released the Signature series, a range of speakers designed for hi-fi and home theater systems. Combining classic design with tried and trusted technologies, the Polk Audio S20 is a compact speaker within the Signature series. Although the S20 doesn’t benefit from the reputation of a mainstream brand, it appears to be well built. The Polk S20 is sold for under 350€ for a pair.
Here is a bit of background information if you are not familiar with Polk Audio: the American loudspeaker manufacturer was founded in 1972. During its golden age, Polk was designing speakers loaded with sometimes more than 10 woofers and just as many tweeters. It was a different era…Polk speakers boast a rather classic design and the drivers used are also quite traditional. The common thread for all of the manufacturer’s speakers is that they are adjusted to ensure solid lows combined with clear and soft highs. We already had the occasion to observe and appreciate the Polk sound signature with the Polk Magnifi Max SR soundbar.
Polk Audio S20: bass driver
The Polk Audio S20 speaker is fitted with a 6.5” (16.5 cm) driver featuring a mica-reinforced polypropylene cone loaded in a generous amount of air. It’s a well-known principle; a driver needs air to benefit from proper extension on the lows and to ensure proper efficiency. Polk states that the S20’s frequency response reaches down to 39 Hz in the lows. It seems like a rather ambitious rating for a compact speaker, especially when it comes to delivering sound at a proper level. Nevertheless, the speaker features a Power Port vent located behind the speaker that is designed to ensure optimal direction of low frequencies.
Polk Audio S20: tweeter
The 1” (25 mm) dome tweeter is made of polyester, which ensures superior dampening as well as a delicate and soft restitution of high frequencies. The Polk S20 compact speaker is Hi-Res Audio certified, which means its frequency response extends to 40 kHz. However, the response curve is not provided.
In a nutshell, the Polk S20 has a frequency response of 39 Hz – 40 kHz and features a sensitivity rating of 88 dB @ 1 kHz.
Polk Audio S20: test conditions and listening impressions
We connected the Polk Audio S20 speakers to the Yamaha MusicCast CRX-N470 amplifier using Viard Audio Silver HD12 speaker wire. We listened to CD quality and high resolution FLAC files stored on a DLNA server (Emby).
Listening to the Polk S20 is an enjoyable experience. The highs are clear, the lows benefit from solid foundations, and the mids and high-mids enjoy a proper amount of energy. The sound is well balanced and the slight emphasis on the highs doesn’t affect the overall coherence of the sound restitution. Truth be told, the tweeter brings extra room to the sound restitution which participates in making the sound stage even more spacious. A rather uncommon feature for a speaker in this price range.
Polk Audio S20: compared to…
Q Acoustics 3020i: the Polk S20 benefits from a more open sound stage and provides more oomph in the lows. The Polk Audio S20 is also a lot more temperate in the mids and, as a result, offers a more pleasant listening experience. Polk has the upper hand with its more dynamic restitution.
Monitor Audio Monitor 100: the Polk S20 is less stern and dry. It also benefits from smoother and more delicate highs. For an articulate listening experience, the Polk Audio S20 is the way to go.
Klipsch RP-150M: the Polk S20 is a bit more shy and does not have quite the same punch as the RP-150M. While the Polk speaker benefits from a better extension in the highs and lows, the Klipsch RP-150M wins this round when it comes to the mids (the acoustic horn has an important part to play in this).
Jamo Concert C93: the Polk S20 offers a comparable sound restitution but benefits from broader lows. The Polk S20’s woofer is the winner of the round.
B&W 686 S2: the Polk speaker is less rigorous than the model from B&W when it comes to high frequencies. The B&W 686 S2 is more refined while the Polk S20 is the more expressive of the two.
Polk Audio S20: conclusion
The Polk Audio S20 is a very interesting value. We enjoyed the qualities of its tweeter and the details it brought to the sound stage. The lows are generous yet well integrated. It is difficult to find drawbacks to this speaker, which will pair-up really well with a hi-fi amplifier (D-Stream Wamp 200SB, Marantz M-CR511, Emotiva BasX A-100, …) or with a mid-range AV receiver. (Yamaha MusicCast RX-V483, Denon AVR-X550BT, Onkyo TX-NR676, …).