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Vanishing Series In-Wall Center-Channel Speaker: The Polk Audio Vanishing Series in-wall center-channel loudspeaker (255c-RT) features a precision-engineered minimally flanged design and Polk's exclusive Sheer-Grille, which protrudes only 7mm from its surroundings. Installing virtually-flush in your wall, the Polk Audio Vanishing Series in-wall center-channel loudspeaker offers a one-cut, drop-in installation and rotating cam stabilizing system. The Polk Audio Vanishing Series in-wall center-channel loudspeaker provides superior high-performance sound from its dual 5.25" woofers and aimable 1" tweeter, with Reflective Room (Tweeter) Compensation control.

Driver Technology
Infinite Enclosure Design
Connections
Mounting Options

Driver Technology

Dynamic Balance Technology: Laser imaging technology allows Polk Audio engineers to see the entire vibrating surface of a driver and tweeter; they can actually see the resonance develop on the speaker cones-resonance that is the root cause of loudspeaker distortion. Being able to see the resonance develop, they then determine the Dynamic Balance of high-tech materials, geometry and construction that together effectively tune out the offending resonance. Exclusive Dynamic Balance Composite Material Technology delivers sound that is effortlessly clean and clear, even at lifelike volume levels.

Klippel Optimized Motor Structures: The Klippel Distortion Analyzer allows Polk engineers to optimize each driver's motor structure, voice coil alignment and suspension to insure smooth, unimpeded movement even at extreme listening levels. This is especially important in the shallow depth area afforded an in-wall built-in loudspeaker.

Dual Midranges: The Polk Audio Vanishing Series in-wall center-channel loudspeaker employs two 5.25" Dynamic Balance mineral composite polypropylene cone midrange drivers with rubber surrounds for a smooth, consistent frequency response. Each midrange driver features a lightweight, strong composite basket that work in conjunction with Klippel Optimization to keep moving parts in rigid alignment while further damping performance-robbing resonances.

Silk Dome Tweeter: The Vanishing Series in-wall center-channel loudspeaker employs a 1" Dynamic Balance silk polymer composite dome tweeter for crisp, clear imaging. The high-performance silk dome tweeter in the Vanishing Series in-wall center-channel loudspeaker features a 15° swivel housing, for more direct high frequency control, excellent off-axis imaging and more placement flexibility.

Reflective Room (Tweeter) Compensation Control: An easily accessible Reflective Room (Tweeter) Compensation switch allows you to make advanced audio tweaks to optimize the sound for any installation. Use the Reflective Room (Tweeter) Compensation switch to digitally compensate for harsh reflective surfaces. It doesn't merely reduce high frequencies; it actually allows you to "notch-out" a specific area of the spectrum (3500-6000Hz) where room acoustics most often interfere with performance.

• Filter Setting: If your listening room is very reflective, with smooth sheetrock walls, hardwood floors, and non-cushioned furniture, the sound will be overly "bright" and unnatural. Selecting the "Filter" setting compensates for the effect of reflectivity in a hard room. Tweeter attenuation flattens room response, without hindering higher frequency response, for warmer, more realistic sound and more accurate imaging.
• Normal Setting: If your room is not reflective, with curtains, artwork, lots of cushioned furniture and carpeting, sound will be absorbed by the room, resulting in more realistic reproduction and more accurate imaging. In this case, select the Normal setting.

Timbre Matched: The Polk Audio Vanishing Series in-wall center-channel loudspeaker is timbre-matched to Polk Audio's high-performance RTi bookshelf and floor-standing loudspeakers. This allows you to match them to an existing Polk Audio home theater speaker system and enjoy seamless blending from speaker to speaker. Timbre-matched speaker components will insure the same true response throughout your system.

Frequency Response: The overall frequency response of the in-wall center-channel loudspeaker is 30Hz to 27kHz, and the -3dB frequency response is 50 to 25kHz.

Infinite Enclosure Design

Infinite Baffle Tuning: Infinite Baffle Tuning uses the virtual enclosure of the in-wall space for deep bass response and superior overall sound.

Wafer-Thin Sheer-Grille: The Polk Audio Vanishing Series in-wall center-channel loudspeaker features Polk's exclusive wafer-thin Sheer-Grille, a magnetically-secured grille that protrudes only 7mm from its surroundings. The Sheer-Grille can be painted to match your décor, making it virtually indistinguishable from its surroundings. The Sheer-Grille has nearly transparent, ultra-small perfs, and are acoustically inert, for dynamic, unimpeded sound and more uniform coverage, even in larger rooms.

Note: We highly recommend you use a can of spray paint matched to the wall color you want the Sheer-Grille to blend with. Never use a brush or roller to paint the grille, as this will clog the perf holes.

Connections

Gold-Plated Spring-Loaded Posts: The in-wall center-channel loudspeaker has a gold-plated pair of spring-loaded binding posts that can accept up to 12-gauge wire, single banana plugs, or pin connectors.

Mounting Options

Applications: You can use the Polk Audio Vanishing Series in-wall center-channel loudspeaker to complete a system of traditional loudspeakers or in-wall speakers, by adding an inconspicuous center-channel speaker.

Placement: The in-wall center-channel loudspeaker is designed to be installed above or below your flat-panel television. Install the in-wall center-channel loudspeaker as close to ear level as possible. If the speaker needs to be installed lower or high than ear level, then aim the tweeter accordingly.

Note: Do not block the in-wall center-channel speaker with your TV or furniture, as this will disrupt and muffle the sound.

Rotating Cam System: The Polk Audio in-wall center-channel loudspeaker utilizes a rotating cam system to ensure a secure, vibration-free installation.

Installation: The Polk Audio Vanishing Series in-wall center-channel loudspeaker (255c-RT) can be installed in new or existing construction.

• Existing Construction: In existing walls, use the included cardboard template for one-cut, drop-in simplicity. Achieve secure, vibration-free efficiency with a simple turn of Polk's Rotating Cam system (5 rotating cams).
• New Construction: Pre-construction brackets (sold separately) are available for new-build or open-wall retro-fitting.

Dimensions: Crutchfield Measurements.