Surrounds
F/XiA4
Timbre-Matched Bipole/Dipole Surround Loudspeaker
11 3/8" W x 12" H x 7 7/16" D
28.89cm W x 30.48cm H x 18.89cm D
Full Fidelity and High Performance
The F/XiA4’s engine is the dual Dynamic Balance® 1-inch dome tweeter design and a 5 1/4-inch Dynamic Balance driver that produces believable real-life effects at prodigious volumes. The selectable bipole/dipole function allows you to configure it to your space and 7.1 systems. The smaller cabinet enables it to fit in more places.
The F/XiA4 Features:
The trapezoidal shaped cabinets aim the drivers and tweeters in opposing directions to produce a more realistically diffuse wavefront and wide, lifelike imaging of surround sound. Keyhole slots make mounting a snap.
With the flip of a switch, our dipole/bipole circuitry changes the soundfield from direct to indirect radiation patterns enabling you to place the surround speaker beside or behind you depending on your listening room setup.
Klippel motor optimization uses laser measurement technology to ensure a smooth excursion path at either end of the volume spectrum for uniform performance at both low and high volumes.
Polk’s proprietary, patented Dynamic Balance technology allows our engineers to design out distortion-causing driver and system resonances, so you only hear the good sounds.
Durable, computer-modeled, injection-molded butyl rubber surrounds suppress unwanted cone resonances for a lifetime of reliable sound.
The F/XiA Cascade Tapered Crossover eliminates the comb filtering and beaming, common to multi-driver speakers, which degrades the quality of the audio and collapses the soundstage.
Patented Acoustic Resonance Control® (ARC) technology suppresses cabinet resonance that causes distortion to ensure clear and natural sound.
Computer-modeled anti-diffraction grilles enhance the good looks while minimizing sonic interference.
All Polk loudspeakers are timbre-matched within their series, designed with the same components throughout, to achieve seamless speaker-to-speaker blending effects in multi-channel systems.
Gold-plated, professional-style 5-way binding posts offer the most secure connection options.
All Polk products are made using the best materials and the most advanced manufacturing techniques. They pass the industry’s most exhaustive quality tests, including drop testing, extreme signal response and UV & salt exposure testing. Polk loudspeakers are built to perform for a lifetime.
Driver Complement | |
|---|---|
| Tweeter | |
| Quantity | 2 |
| Diameter | 1" (2.54cm) |
| Type | Dynamic Balance silk polymer composite dome tweeters |
| Mid / Woofer | |
| Quantity | 1 |
| Diameter | 5 1/4" (13.34cm) |
| Type | Dynamic Balance driver with polymer composite cone and rubber surround |
Electrical | |
|---|---|
| Total Frequency Response | 50Hz-27kHz |
| Upper -3dB Limit | 26 kHz |
| Lower -3dB Limit | 60 Hz |
| Nominal Impedance | 8 ohms |
| Efficiency | 88 dB |
| Recommended Amplifier Power | 20-125 watts per channel |
| Inputs | 5-way binding posts |
Dimensions | |
|---|---|
| Cabinet Dimensions | |
| Height | 12" (30.48cm) |
| Width | 11 3/8" (28.89cm) |
| Depth | 7 7/16" (18.89cm) |
| Enclosure Type | |
| Mid-High Array Enclosure Type | Vented |
| Mounting Options | Integrated keyhole slot for wall mounting |
| Product Weight (each) | 9 pounds |
Shipping | |
|---|---|
| Unit of Measure | Pair |
| Total Shipping Weight | 25 pounds |
Warranty | |
|---|---|
| Speaker Warranty | 5 years parts and labor (original purchaser) |
Specifications, dimensions and features subject to change without notice. For more information call us at 1-800-377-7655 (USA and Canada). Outside of North America call +1 (410) 358-3600.
Customer Reviews
7 reviews with an average of 5
Write your own reviewby matyeo, November 19, 2008
7 out of 10 people found this review helpful.Strengths:
super great quality of hi freq. very clear sound efect detection..
Weaknesses:
none
Review:
i replaced my previous speaker mirage omnisat v2 with this speaker, after 1 month this is the perfect sorround speaker for me , i can feel great quality of hi-freq. recomanded to everybody. sound without quality is just noise...
by Vico38, August 29, 2008
5 out of 5 people found this review helpful.Strengths:
Stylish, Sound is nuanced and gripping. love the dipole/bipole switch, but you are going to want to keep them dipole.
Weaknesses:
None.
Review:
I installed these to complete my Polk Audio 5.1 setup and the surround soundstage has opened up to the point of amazing.
by MUSIC MIKE, December 29, 2010
4 out of 4 people found this review helpful.Strengths:
Has an ambient feel and not such a direct sound as bookshelves would have.Despite having only one driver, these outperformed the older true bipolars I had with two drivers each.They look nice too.I tried the larger A6s but the sound was only slightly better so I brought the larger ones back.
Weaknesses:
It doesn't make sense why Polk designed these with one driver when most speaker enclosures this big have two. Not a biggie as they still sounded better than my older surrounds for some reason.
Review:
Bought these for Boxing Day last year and still blown away. The bipole dipole switch doesn't do much though but not a big deal.I tried the larger A6s to match better with the A9s but the sound was only marginally better, so I stuck with the A4s.
by Mario Balari, March 10, 2008
2 out of 5 people found this review helpful.Strengths:
Exelente sonido, gran terminacion.
Weaknesses:
Ninguna objeción..
Review:
Con estas unidades completo mi sistema Polk. Realmente estoy sorprendido de el cambio del sonido que obtuve al reemplazar mis viejos traseros Sony 550 Las recomiendo ampliamente.
by Chris Ekstrom, December 31, 2008
1 out of 1 people found this review helpful.Strengths:
I notice no deficiencies anywhere. They handle highs and lows incredibly well. I have heard high end European speakers at four times the cost that don't come close to what Polk has produced. When I finally upgrade my towers I know which way I am going.
Weaknesses:
Absolutely none.
Review:
Hello,I just purchased a pair of Polk Audio FXi A4 surround sound speakers. To put it mildly,these speakers are simply awesome. I have a pair of Paul Barton towers, Boston Acoustics center & sub. These surrounds compliment my system like no other surrounds I've had.
by paddo, April 10, 2008
1 out of 3 people found this review helpful.Strengths:
Great sound powerfull for size and very stylish speakers
Weaknesses:
None that I know of.
Review:
I have spent alot on my home system needed two surrounds to compleat it and I am very happy will them.
by Raul Maldonado, January 15, 2009
1 out of 2 people found this review helpful.Strengths:
Rediculous clarity and detail. Highly recommended will not buy anything else but Polk.
Weaknesses:
absolutely nothing has a weakness with Polk Audio to me.
Review:
By far Polk has made listening to all sorts of music and watching tv and bluray movies a whole different world and experience. These speakers paired up with RTi8 towers, just simply put, optimises sound clarity and detail. All I have to say is that, I now need a CSi A4 to complete my set up. Equipment: Pioneer Receiver 7.1 front bi-amp Polk RTi8 front JBL center (for now) FXi A4 rears Martin Logan Dynamo sub
View all Professional Reviews
Professional Reviews

"In the deer-chase scene early in I Am Legend, the zooming, roaring, and screeching of Will Smith's Mustang dominated the aural landscape, echoing impressively through the empty canyons of midtown Manhattan. And the sound effect of clattering hooves managed to track the fast-moving deer without sharply hot-spotting one or another speaker."
Mains
Center
Subwoofer(s)
F/XiA4 Media
F/XiA4 Literature
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Frequently Asked Questions
- What speaker should I buy for the surround channel?
- Why are my speakers distorting and popping?
- What wire should I get? What gauge?
- How do I choose between all the different home audio speakers?
- What is dipole and bipole and how are they different?
- How long is the warranty on Polk loudspeakers?
- How do I obtain service for my loudspeakers?
- Why did my speakers break?
- Where do I place the surround speakers in my room for the best performance?
- What type of speaker wire should I use?
- How do I get the little plastic inserts out of the binding posts so I can use banana plugs?
- What is the Klippel Distortion Analyzer?
