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The Polk Audio CS400i is a high-performance, two-way center channel speaker featuring dual 6.5-inch Dynamic Balance mid-woofers and a 1-inch tri-laminate dome tweeter for detailed, clear dialogue. Designed for superior home theater performance, it includes rear Power Port technology for efficient bass, Acoustic Resonance Control (ARC) to minimize cabinet resonance, and supports bi-amping/bi-wiring.
Key Features and Specifications:
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Drivers: Two 6-1/2" (16.5cm) Dynamic Balance drivers and one 1" (2.54cm) trilaminate dome tweeter.
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Performance: 50 - 25,000 Hz frequency response (-3dB) with 91dB sensitivity.
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Power Handling: 20 - 250 watts per channel.
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Technology: Rear-mounted Power Port for improved, punchier bass and ARC (Acoustic Resonance Control) to reduce cabinet resonance.
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Design: Video-shielded, black vinyl finish, and dual 5-way binding posts for flexible wiring.
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Size: The unit is relatively large (18-3/4"W x 8-11/16"H x 13-3/4"D).
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Compatibility: Designed to match the Polk Audio RT2000i, RT1000i, RT800i, RT600i, and RT55i speaker lines.
The CS400i was known for being a major, heavy, and robust center channel in its series, often regarded for producing clear, full sound for movie dialogue and effects.
Please note: Collection from our Murarrie showroom or freight at buyer's expense. We do not offer free shipping on traded equipment.
Contact The Audio Tailor today to arrange an audition.
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Polk Audio emerged in 1972 from the inventive spirit of three Johns Hopkins University graduates—Matthew Polk, a physics major, George Klopfer, and Sandy Gross—in Baltimore, Maryland. What began as a modest venture building public address systems for local events evolved into a dedicated speaker company after an initial contract fell through, leaving the founders to sell their redesigned cabinets directly. Fueled by passion for music and hi-fi innovation, they secured Small Business Administration loans, relocated operations, and rapidly scaled production, hitting $1 million in revenue by 1976 and earning a spot on Inc. magazine's list of America's fastest-growing private companies.
The brand has long focused on loudspeakers as its cornerstone, pioneering models like the Monitor 7 series for balanced dynamics, deep bass, and high-volume performance that bridged European refinement with American power. Polk expanded into automotive audio through partnerships like MOMO in 1999, while maintaining a core lineup of home speakers, including innovative SDA technology for enhanced soundstaging. Though not delving into amplifiers, turntables, DACs, headphones, or cables, their emphasis remains on reliable, high-fidelity transducers engineered for generations-spanning accuracy.
Polk Audio holds a solid mid-tier position in the hi-fi market, prized by enthusiasts for value-driven performance sold through specialty stereo shops and big-box retailers like Best Buy. Once publicly traded on NASDAQ in 1986 before going private in 1999, the brand now operates under Sound United, upholding its legacy of accessible excellence without chasing ultra-high-end exclusivity or vintage obscurity.
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