The Polk Signature Elite ES55 is a tower speaker that features a Dynamically Balanced Acoustic Array, 2.5-Way Cascading Crossovers and Power Port Bass Enhancing Technology to deliver high-resolution cinematic sound in a spacious, lifelike soundstage. Enjoy hi-res music from services like Apple Music, Tidal, Amazon Music HD, Spotify & more, along with the soundtracks of the latest ultra-HD movies