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Polk Audio LSiFX

Dipole/bipole surround speakers

3 Reviews

Item # 107LSIFX

This item is no longer available.

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Our take on the Polk Audio LSiFX

Exploded speaker

Polk's Ring Radiator tweeter produces crystal-clear highs.

Experience your movie soundtracks unlike ever before

When it comes to making a movie soundtrack come to life all around you, it's hard to beat dipole/bipole surrounds like the LSiFX speakers from Polk. These flexible speakers have 45° angled driver arrays, giving you the perfect mix of direct and indirect sound. Each array sports a 1" Ring Radiator tweeter and a 5-1/4" aerated polypropylene Dynamic Balance driver — the incredibly robust, natural sound will envelop you.

Versatile design and placement

Grill off

When it comes to placement and listening preferences, you can change the phase relationship between driver arrays with the handy dipole/bipole switch. A bipole setting is great for placing the speakers behind your listening position, and provides clear, directional sound. Dipole usage, on the other hand, is ideal for placement to the side of your listening position and results in a more diffuse soundfield. Wall-mounting is simple, thanks to the built-in keyhole slot. Plus, with a sophisticated, high-gloss black finish, the LSiFX makes a nice addition to any room. Timbre-matched to Polk's LSi line of speakers.

Priced per pair

Product Highlights:

  • bass-reflex
  • frequency response 52-26,000 Hz (-3dB)
  • 4-ohm impedance; these speakers must be powered using high-current amplification
  • sensitivity 88 dB
  • handles up to 200 watts
  • keyhole slot
  • high-gloss black finish
  • 5-way, gold-plated binding post terminals
  • 13-1/16"W x 15"H x 10"D
  • warranty: 5 years
  • Our 60-day money-back guarantee

Couple these speakers with the rest of the Lsi family and a nice subwoofer and the results will blow you right out of your recliner. Regardless if your listening to music or watching a movie. Polk Audio IS the Best!

Shotster36, Morris, IL

What's in the Box:

  • 2 LSiFX surround sound speakers
  • 8 Adhesive backed black rubber feet
  • Template for wall mounting
  • Manual
  • Product registration survey
  • On line registration information

Polk Audio LSiFX Reviews

Average Customer Review(s):

(3 Reviews)

Ear-gasmically fantastical!!!

Joe from Mansfield, TX on 6/30/2009

Real words can't describe the incredible sound emitted from these speakers. The entire LSi series from Polk Audio is amazing. I use the LSi 9, LSi C, and LSi FX with a sub and Onkyo receiver. Everything I listen to is reproduced more clearly and accurately than with any other speaker brand that I've ever heard.




Shotster36 from Morris, IL on 1/21/2007

Crutchfield Customer Review (What's this?)

Couple these speakers with the rest of the Lsi family and a nice subwoofer and the results will blow you right out of your recliner. Regardless if your listening to music or watching a movie. Polk Audio IS the Best!



awesome clear surround / loud speakers

chris from lantana, fl. on 2/27/2005

Crutchfield Customer Review (What's this?)

these surrounds are awesome. the highs, mids and even bass is just like the rest of the lsi series ( clean, clear and tight ). I also use these speakers on my other main channels for music. <BR>If you want the best surrounds these are the ones.<BR>at 4 ohms it turns 170 watts per channel into 230 watts.<BR>I wouldnt trade my entire lsi series for any speaker.<BR>I tried the entire csi series first and was not happy HOWEVER, because Crutchfield offers such great service, I sent the entire csi series back and purchased the entire lsi series. Perfect speakers and perfect service.




Hands-on research

Product Research

Driver Technology
Enclosure Design
Mounting Options

Driver Technology

Tweeter: The LSiFX uses the same Ring Radiator tweeters as the rest of the LSi Series. This produces a seamless front stage and lifelike surround environment. The ultra-light woven Ring Radiator Diaphragm delivers flat response, precise detail and overall accuracy. A High Frequency Waveguide prevents phase cancellations for smooth, uniform frequency response and wide dispersion. A Low Frequency Waveguide promotes laminar airflow between chambers to prevent air turbulence. This feature serves the same function as Power Port for Polk's bass systems.

Basket: The cast aluminum driver baskets resist flexing and "ringing" for ultra-tight bass and coloration-free midrange.

Timbre-Matched: Timbre-matched with the LSi Series for a seamless, realistic surround sound experience.

Enclosure Design

Enclosure: The speaker has a triangular shape with the speaker faces angled at 45 degrees. Both faces have a tweeter and a woofer and one face also has a switch for selecting Dipole or Bipole operation.

Grille: The open architecture low diffraction grille is used for spacious imaging.

Power Ports: Dual rear-firing Power Ports built into the back plate provide distortion-free bass and surprisingly deep bass response.


Bi-Amplification: Since this speaker may be bi-amplified, you can improve the sound by using separate amplifiers for the tweeter and woofers. Note that the jumpers connecting the 2 pair of 5-way binding posts must be removed when bi-amplifying.

Mounting Options

Placement: Designed for use only as rear surround speakers.

Wall Mounting: The Power Ports double as convenient wall mounting brackets with key hole slots.

Dipole/Bipole Switch: There is a switch that allows the speaker to be used as a Dipole (out of phase) or Bipole (in phase) speaker. If you're mounting the speakers on the side walls in line with your listening position, the dipole mode will create a diffuse, ambient soundfield. If you're placing them behind your position, the bipole mode fires the drivers in phase to flood your room with surround sound. When used with a Dolby Digital system, the surround speaker setting should be set to small.

Our Product Research Team

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