The Atrium 45 speakers have a wide dispersion pattern, and they're very efficient, operating on as little as 10 watts per channel. They're designed to deliver good sound quality across a large listening area, but Polk recommends multiple-pair setups if you want high sound levels in an outdoor setting, as sound tends to dissipate more quickly outdoors than in.

The speakers' white finish is paintable to match your decor or trim color--you can even paint them green to blend with foliage. Their sculpted front baffle and rounded enclosures minimize diffraction (sound reflecting off of hard edges) for more open and lifelike imaging, and their rustproof aluminum grilles offer 55 percent open area for better high-frequency response than speakers with denser grilles.

Sealed-enclosure (acoustic suspension) cabinets result in taut bass, and the speakers' 2-way design incorporates a 4.5-inch long-throw polymer cone driver with butyl-rubber suspension and a .75-inch dome tweeter with a neodymium magnet to broadly distribute high frequencies. Gold-plated, 5-way binding post terminals will never corrode. The plugs also allow hookups in a range of methods, including convenient banana-plug-terminated speaker cable.

The Atrium 45 meets or exceeds ASTM D5894-UV Salt Fog, Mil standard 810 Immersion and Mil standard 883 Method 1009 8 for salt and corrosion tests.

What's in the Box
Two speakers (each with detachable metal grille and built-in mounting bracket) a user's manual, and warranty information.