Polk FXi A4 Dipole Bipole Surround Speakers, Pair
$395.00
Two 1-inch silk/polymer dome tweeters aimed 45 degrees apart and a 5.25-inch Dynamic Balance woofer in a triangular, side-ported cabinet, with a switch that moves them between dipole and bipole. 88 dB, 8 ohms, 20 to 150 watts, keyhole-slotted for wall mounting. Voice-matched to Polk’s RTi and CSi models. Good working condition, fully tested.
1 in stock
Polk FXi A4 Dipole Bipole Surround Speakers Pair
Versatile Polk Audio FXi A4 dipole/bipole surround speakers with switchable modes, dual tweeters, and Dynamic Balance drivers delivering enveloping rear-channel effects for immersive home theater performance.
Add the Polk FXi A4 surround speakers to your home theater system and enjoy dramatic rear-channel sound effects with your favorite movies. These cleverly designed speakers feature two 1-inch silk/polymer dome tweeters aimed 45 degrees from each other, creating an ideal mix of direct and indirect sound that fully immerses you in the movie action. A unique triangular cabinet design positions a 5.25-inch Dynamic Balance woofer and tweeter on one side, with a port and second tweeter on the opposite side, delivering spacious, three-dimensional imaging that wraps around your listening position. The dipole/bipole switch provides flexible placement options: set them to bipole mode for rear-wall mounting with distinct, directional sound, or switch to dipole mode for side-wall placement to create a more diffuse soundfield for convincing wraparound effects.
Polk carefully designed the FXi A4 drivers using laser testing to help identify and eliminate resonance points, ensuring clear, detailed highs and natural midrange reproduction. The acoustically tuned bass-reflex cabinet with side-mounted port tube delivers increased and extended bass response down to 60 Hz, adding weight and impact to explosions, musical scores, and low-frequency effects. Each tweeter uses a heat sink on the Neodymium magnet for superior heat dissipation, power handling, and reliability during extended listening sessions. The acoustically inert MDF cabinets fight internal vibrations that can compromise performance, while floating anti-diffraction grilles minimize grille diffraction for spacious imaging. At 88 dB sensitivity and 8-ohm impedance, the FXi A4 pairs easily with receivers and amplifiers from 20–150 watts, making them compatible with a wide range of home theater systems.
Voice-matched to Polk’s RTi tower and bookshelf speakers and CSi center channel speakers, the FXi A4 ensures seamless tonal integration across your entire surround system. Gold-plated 5-way binding posts accept bare wire, spade connectors, or banana plugs for secure, high-quality connections. Integrated keyhole slots make wall-mounting straightforward, though the side-ported design means they can be mounted closer to walls than rear-ported speakers without compromising bass response as severely.
Key Specifications:
Design: Dipole/bipole surround speakers with switchable mode
Drivers: Two 1-inch silk/polymer dome tweeters with Neodymium magnets and heat sinks, one 5.25-inch Dynamic Balance polymer composite woofer
Frequency response: 60–26,000 Hz (-3 dB), 50–27,000 Hz (total)
Sensitivity: 88 dB
Impedance: 8 ohms nominal
Recommended amplifier power: 20–150 watts per channel
Enclosure: Bass-reflex (ported) design with acoustically tuned side port
Terminals: Gold-plated 5-way binding posts
Mounting: Integrated keyhole slot for easy wall-mounting
Voice-matching: RTi tower and bookshelf speakers, CSi center channel speakers
Grille: Floating anti-diffraction design
Finish: Black
Condition: Good working condition, fully tested
Dimensions: (Width x Height x Depth) 287 x 306 x 198 mm (11.31 x 12.06 x 7.81 inches)
Weight: 4.08 kg (9 lbs) each
At 9 lbs per speaker, the FXi A4 offers substantial cabinet construction and driver mass that contribute to extended bass response and dynamic capability, while remaining manageable for secure wall-mounting in real home theater rooms.
These Polk Audio FXi A4 dipole/bipole surround speakers deliver the enveloping, three-dimensional soundfield that makes movies come alive, with flexible placement options, voice-matched performance to Polk’s RTi and CSi series, and quality construction that ensures years of reliable home theater enjoyment.
Backed by Radique Audio’s 90-day warranty and our perpetual trade-back policy, you can purchase with confidence; asking $395.
| Weight | 21 lbs |
|---|---|
| Dimensions | 22 × 15.4 × 16.1 in |
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