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Polk Audio LSi M 703
Bookshelf speaker (Mount Vernon Cherry)
Item # 107LSI703C | MFR # AM7312-A
This item is no longer available.
Our take on the Polk Audio LSi M 703 by Crutchfield's Kristen Schaub
Remarkably realistic performance and a compact footprint
Polk's LSi M 703 gives you the kind of high-end performance that's characteristic of the LSi M line's larger floor-standing model, but in a smaller, more flexible bookshelf speaker. You'll hear a wide, deep soundstage with realistic imaging fleshed out in pinpoint detail, and complemented by surprisingly deep bass — even without a sub. Use a pair of LSi M 703s to create a compact stereo music system or as front speakers in a high-end home theater system.
Building upon the widely acclaimed LSi family of speakers, the LSi M series incorporates the latest developments in speaker technology, fitted into a newly designed enclosure that's beautifully sculpted and luxuriously finished.
Polk's Dynamic Sonic Engine: The speaker within a speaker
Like Polk's larger, floor-standing LSi M models, this smaller bookshelf speaker uses a Dynamic Sonic Engine. Made up of a 3-1/4" midrange driver and a 1" ring radiator tweeter in its own acoustically sealed enclosure, this tightly spaced duo acts like a "mini-monitor." The precise alignment of the midrange and tweeter allows them to disperse sound over a wide, uniform area with excellent off-axis response in the critical 200 Hz to 2,000 Hz midrange.
The ring radiator tweeter features several improvements from the version in the earlier LSi line. A slight reshaping of the tweeter's bullet-shaped phase plug allows it to move even farther out of the baffle, while a redesigned diaphragm has made the tweeter even more efficient.
It even has its own tuned enclosure within the Dynamic Sonic Engine. These changes result in higher power handling, extended dynamic range, improved dispersion, and extended high-frequency response — all the way up to 30,000 Hz!
Advanced driver material for even more realistic sound
The original LSi speakers featured a light, stiff mineral-filled polypropylene cone that was "puffed up" with injected air to form a honeycomb-like structure. The new super cell aerated polypropylene uses larger "puffed cells" to create a cone material that's thicker yet lighter than the original. It's used in both the midrange and woofer, allowing them to move faster and with more efficiency.
This speaker also uses proprietary Orth Crossovers to send the right frequencies to the right drivers, making it extremely efficient and easier for your receiver or amplifier to drive.
PowerPort technology for smooth, deep bass
Like all LSi M speakers, the 6-1/2" woofer has its own PowerPort®. Designed exclusively by Polk, this specially designed "cone" at the mouth of the bass port directs moving air to eliminate bass-stealing turbulence. No turbulence means no wasted power, which means more efficient bass response. You'll hear surprisingly deep bass for a bookshelf speaker that blends smoothly with the mid- and high-frequencies.
Careful cabinet design with a stunning real wood veneer
The '703 cabinet is made of heavily braced 3/4" thick MDF with an even thicker front baffle (1-1/4") to keep distortion to a minimum. Each driver has its own separate, non-parallel chamber to increase the efficiency of each driver and eliminate internal resonances and standing waves. Dual gold-plated binding posts let you bi-amp or bi-wire this speaker for even better performance.
The magnetic grille easily snaps on and off, and it measures less than 1mm thick, so it won't interfere with the sound. And finally, the curved cabinet is finished with a furniture-grade, real-wood veneer that's hand-polished to achieve a gorgeous glow in your home.
Complete your home theater system
Achieve startling realism and seamless surround effects when you build a complete LSi M system. All LSi M models feature the same components and tuning, so you can combine the '706c center channel with any combination of bookshelf or floor-standing speakers in the front of your room, and either additional bookshelf speakers or dedicated surround speakers in the back of your room for wraparound sound effects.
Smooth sound quality with just enough bass to sound complete when listening to all genre's of music.
denise, Jamaica, NY
What's in the Box:
- 1 Bookshelf loudspeaker (cherry)
- Magnetic grille (black)
- 4 Self-adhesive rubber feet
- Owner's Manual CD-ROM
- Quick Start Guide
- "Read First" note
- Thank You letter
- frequency response 50-30,000 Hz (-3dB)
- handles 20-200 watts
- sensitivity 88 dB
- 8-ohm impedance
- 1" ring radiator tweeter
- 3-1/4" super cell aerated polypropylene midrange
- 6-1/2" super cell aerated polypropylene woofer
- PowerPort® technology (for the woofer only) improves bass response
- dual 5-way gold-plated binding posts allow bi-wiring or bi-amping
- hand-rubbed lacquer finished real wood veneer
- 8-7/8"W x 16-3/4"H x 14-5/8"D
- weight: 29.6 lbs.
- warranty: 5 years
- Our 60-day money-back guarantee
Polk Audio LSi M 703 Reviews
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Features and Specs
|Tweeter Type||Ring radiator|
|Tweeter Size (inches)||1|
|Midrange Size (inches)||3.25|
|Woofer Size (inches)||6.5|
|Woofer Composition||Super cell aerated poly|
|Frequency Response||50-30k Hz|
|Mounting Bracket Included||No|
|Recommended Stand Height (inches)||30-36|
|Parts Warranty||5 Years|
|Labor Warranty||5 Years|
Performance Objectives of the Polk Audio LSiM Series Loudspeakers: The LSiM series loudspeaker is Polk Audio's best high-performance loudspeaker. Polk Audio designed the LSiM series loudspeakers to create a sound that virtually transports you to the scene of the recorded performance. It was engineered & created with the following performance objectives in mind.
- Pleasing tonality, even during extended listening at performance levels.
- Crisp, lifelike impulses, transients & coherent detail without any unnatural ringing or decay.
- Natural reproduction of complex low frequency instruments & special effects.
- Uniform sonic representation within the listening area & immersive spatial impression.
- Reproduce concert/theater levels while maintaining linearity and accuracy.
- Compatibility with a wide array of electronics both past, present & future.
- Work as promised for many years of enjoyment (5 year parts & labor warranty).
Dynamic Balance: Dynamic Balance is a proprietary Polk Audio technology using laser imaging to determine what combination of speaker materials create the least amount of resonance. Eliminating resonance in speakers results in a wide, smooth response, & low distortion.
3-Way Driver System: The Polk Audio LSiM series bookshelf loudspeaker employs a 3-way driver system for crisp, detailed highs; natural, lifelike midrange; and accurate, dynamic midbass. The bookshelf loudspeaker houses a 1" (diameter) Dynamic Balance Enhanced Ring Radiator Tweeter, a 3.25" (diameter) Dynamic Balance Super Cell Aerated Polypropylene cone midrange driver, & a 6.5" (diameter) Dynamic Balance Super Cell Aerated Polypropylene cone midbass woofer.
Enhanced Ring Radiator Tweeter: The ring radiator tweeter was a vital element in the success of Polk Audio's original LSi Series. Polk Audio engineers have made some nuanced improvements in the design of this tweeter. First, they reshaped the tweeter's bullet-shaped phase plug, allowing it to move farther out of the baffle, improving dispersion and eliminating horn-loading. Next, they opened up the tweeter's face-plate, then redesigned the tweeter's diaphragm roll to make it more efficient and improve dispersion even more. Finally, they gave the new ring radiator tweeter its own tuned enclosure (Dynamic Sonic Engine). This new ring radiator tweeter boasts higher power handling, extended dynamic range, improved dispersion and extended top-end response.
Super Cell Aerated Polypropylene (APP) Cone Woofer: If the perfect cone material is lightweight (for faster, more efficient action) and stiff (for less distortion-causing flex), with enough internal damping to suppress and offset any limitations of its lightweight stiffness, then the Super Cell APP Cone Material is about as perfect as cone material gets. Aerated Polypropylene (APP) is a mineral-filled polypropylene material that's been "puffed up" with injected air to form a honey-comb structure. Polk Audio's original APP cone approached the ideal balance of lightweight stiffness with high damping, along with good resistance to moisture, UV and temperature extremes. Next generation LSiM series loudspeakers employ Polk Audio's next generation of APP Super Cell. In Super Cell APP, the "puffed cells" are larger, for a thicker cone material that actually has less mass than the original APP material. Super Cell APP has larger cells, for lighter weight and more inherent damping, plus uncompromised stiffness, for unsurpassed transient response and resonance suppression.
Butyl Rubber Surrounds: Durable, soft, injection-molded butyl rubber surrounds are tuned to absorb and suppress unwanted cone resonances. Polk Audio's butyl rubber material is impervious to UV, extreme temps & humidity, for a lifetime of smooth, reliable sound.
Extended Linear Motion Voice Coils: Allowing lots of movement in a limited space, ELM Voice Coils power the LSiM series speaker's mid-range & mid-woofer drivers to extend their higher-frequency response with much less impedance.
Cast Aluminum Baskets: These lightweight, cast aluminum baskets provide a rigid structure for precise alignment of the speaker's active parts, for flat response & low distortion, with no mechanical resonances or ringing. The open design provides ample venting for unobstructed linear movement.
Orth Crossovers: The Polk Audio LSiM series bookshelf speaker employs proprietary engineering, designed and patented by Polk Audio to maintain a lower order crossover design & increase power handling. Orth Crossovers feature Mylar/polypropylene capacitors for sparkling highs & Air Core Inductors for superior transparency. Notch Filters and sophisticated Zobel circuits smooth the impedance curve of the system for more efficiency & better high frequency response.
- Tweeter/Midrange Crossover: 2.8 kHz 18 dB/oct
- Midrange/Midbass Crossover: 300 Hz 12 dB/oct
Timbre-Match Series: You can achieve incredible realism & seamless surround effects when you build a complete Polk Audio LSiM series speaker system. All LSiM series speaker models feature the same components & tuning for perfect timbre-matching.
Frequency Response Note: The overall frequency response is 36Hz to 40kHz & the -3dB frequency response is 50Hz to 30kHz.
Real Wood Veneer: The Polk Audio LSiM loudspeaker is finished in a real, natural, furniture-grade wood veneer.
MDF Enclosure: The enclosure is an integral part of the sound design of the Polk Audio LSiM series loudspeaker. All LSiM cabinets are made of .75" MDF, with wide-radius baffles of robust 1.25" MDF. Substantial internal bracing (each driver has its own separate non-parallel chamber) increases efficiency and banishes internal resonances & standing waves, for high power handling and incredible smoothness. Wide-radius baffles, along with zero-diffraction magnetic grilles, help stabilize imaging for a very wide, well-defined soundstage.
Dynamic Sonic Engine (DSE): At the heart of the Polk Audio LSiM series bookshelf loudspeaker is an enclosure-within-the-enclosure design (known as the Dynamic Sonic Engine) that houses the mid-range driver & the ring radiator tweeter. Molded into one rigid piece, the DSE enclosure tapers to a "turbine" that reduces back-wave reflections. The DSE combines its two speakers in an aligned, optimized array for wide, uniform dispersion in the critical 200Hz-2kHz midrange, improving transient response. The combination delivers exact timbre-matching, improved high-frequency dispersion and greater horizontal off-axis response.
Note: The ring radiator tweeter & midrange driver are housed in a separate internal sealed enclosure from the ported enclosure which houses the midbass woofer.
PowerPort Bass Venting: PowerPort Bass Venting is a Patented Polk Audio technology that uses a specially designed "cone" at the mouth of the bass port to direct moving air as it exits the port. Air moving out of a bass port creates turbulence, which can result in boomy distortion & "port noise", especially at high volume. This distortion can cause bass output losses up to 3dB, wasting lots of amp power. To eliminate bass-stealing turbulence at the mouth of the port, Polk Audio engineers designed the PowerPort. It's unique shape promotes "laminar" airflow even in short tube ports by mimicking the properties of longer, flared port openings. No turbulence means no wasted power, which means more efficient bass response.
Zero-Diffraction Magnetic Grille: The super thin (1mm), zero-diffraction grille has no measurable effect on the speaker's response. Completely unobtrusive, stylishly sheer; the grille locks into place magnetically.
Dual Gold-Plated Binding Posts: The bookshelf loudspeaker has two sets of gold-plated binding posts connected by wire-jumpers. The gold-plated binding posts will accept bare wire (16-12 AWG), pin connectors, spade connectors, & banana plugs (single only).
Bi-Wiring/Bi-Amping: Using the dual posts, you can bi-wire or bi-amp the speaker. Bi-wiring or bi-amping the speaker provides improved bass & treble performance. If you decide to bi-wire or bi-amp, you must remove the jumpers between the terminal posts (failure to do this could result in damage to your amplifier and loudspeakers).
- Bi-Wiring: Bi-wiring can provide noticeable improvements in the overall transparency of your loudspeakers. Run separate speaker wires to the low & high frequency drivers from a single amplifier (the upper set of binding posts are for the high frequency drivers; the lower set of binding posts are for the low frequency drivers).
- Bi-Amping: Bi-amping allows you to use separate amplifiers for the high & low frequency sections of your loudspeaker for greater dynamic range & lower distortion. We recommend that your separate amplifiers have identical gain to preserve the speaker's voicing balance.
Color-Coded: The bookshelf speaker's binding posts are color-coded (red/black) for easy identification between positive & negative.
Placement: The LSiM series bookshelf loudspeaker is designed to provide excellent performance on a bookshelf or placed on a floor stand. For best results place LSiM bookshelf loudspeaker so the tweeter height is within 6" of your seated ear height.
Positioning: The LSiM series bookshelf loudspeaker can be used as a front speaker or rear-channel surround speaker.
- Front Application: To enjoy the most realistic stereo image and lifelike sound, place the speakers so that an equilateral triangle is created between the speakers & your favorite listening position. Angle the speakers toward the middle as necessary in order to support a more solid center image. Experiment with the distance between your speakers & both the back/side walls. You'll experience some bass boost with the speakers located closer to walls.
- Rear Application: If you are using your LSiM series bookshelf loudspeaker as a rear channel in a home theater system, it should be placed on the rear or side wall, slightly above (and, on the side wall behind) the listening position. Angle it toward the listening area if possible.
Rubber Feet: The bookshelf speaker comes with 4 self-adhesive rubber feet so it will sit securely on your stand or shelf.
Note: The speaker does not offer any wall-mount options.
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.
Product reviews from the Crutchfield Labs
by Dave Bar
We dissect the Polk Audio LSi M 705 floor-standing speaker to find out what makes it sound good.
Why did you buy this?
After speaking with Stone the rep who gave me great advice and product info I believe my decision was the best for me and my music. Can't wait to spin my vinyl again and rock the house. [ Michael Jun 07, 2017 ]
My main speakers, love the sound with Miles Davis or John Coltrane playing. Very pleasing. The only speakers I own are Polk Audio, like their sound and they fit my budget. [ Scott Jan 04, 2017 ]
The 1/2 list price, 5 star reviews, large bookshelf, Polk history with other speakers, Crutchfield service, and online pro reviews! [ J. PATRICK Dec 21, 2016 ]
I've been listening to a pair of RTi A3's, and a PSW108, thought it was time for a bigger sound. [ Joe Feb 01, 2017 ]
I'm a long time listener of polk speakers I have SDA's it's time to upgrade I like how the LSi M sounds. [ John Nov 09, 2016 ]
Excellent look, performance and size. [ John Jul 25, 2016 ]
I own other polk products it was between these or paradigm prestige 15b [ shannon Jan 18, 2016 ]
FAVORABLE REVIEWS [ ANTHONY Dec 21, 2015 ]
5 questions already asked
4 answers I am considering two of these for my right and left front Chanel's in a 5.1 set up. The other speakers are Polk RTI 100. The system is powered by an Onyko TX NR727. I can't afford to upgrade the rest of the speakers at this price, but thought these would improve the overall sound of my system. However I worry that they might overpower the other speakers. Is this a real concern or will these work well with the rest of speakers? [ Mark Mar 06, 2017 ]
Lsim703 will make a good front set of speakers for a small to medium size room. Not sure if the Lsim703 will over power the RTI 100 because I have not heard them. [ John Mar 08, 2017 ]
In order to achieve the best sound, it is best to timbre match speakers. What that means is if you purchase LSi fronts you should also purchase a rear speaker that is in the LSi series. So I would recommend to purchase the best RTI speaker you can afford. In a 5.1 configuration the center channel is extremely important, followed closely by the right and left front. Hope this helps. [ Daniel Mar 07, 2017 ]
think you will improve overall sound of your system without 703s overpowering other speakers. my own preference would be for a mached system. that said, the 703s ain't cheap [ JAMES R Mar 06, 2017 ]
The overpower is not a concern; but your watts per channel may be! These speakers have a effiency rating of 88! So you need a minimum of 100 watts RMS! With a 5.1 will your receiver put out 100 watts RMS? Great speaker that I push with 125 watts from amp! [ J. PATRICK Mar 06, 2017 ]
Hi, I have bought a pair of these speakers and I can tell you they meet my expectation in terms of quality, clarity of sound, no distortion, and elegance. They are indeed a bit expensive but the sound is equivalent to the one produced by bigger speakers. I really don't regret the investment. I listen various style of music from classical piano to jazz, passing by pop rock and the speakers are very polyvalent. I hope this will help you making your choice. [ Guillaume Jul 28, 2015 ]
Hi William T R! I am passionate about the sound from Polk speakers. I have a center channel in addition to the LSi M 703. They don't just "really sound good" but they sound fantastic. Whether you listen to classical, jazz or rock, the range and clarity of sound from Polk does not disappoint. It is an investment that I cherish each time I crank the volume. [ JEFFREY R Jul 27, 2015 ]
These are well designed speakers. I replaced a set of tall speakers with these and found they supplied all the range in less space. I did get the free Polk subwoofer to supplement my movie watching, but don't need that for music. [ RICH Jul 27, 2015 ]
True, they need to back it up, and I think they do... I think they are reasonably priced... the placement of them will be important as always to get best effect.... since buying these, I've bought some Magnepan 1.7i's and also some Revel F208's... the Revel's cost about $5K, though I got mine for $3K used. I still listen to the Polk's even with more expensive speakers around. The Polk's are good. [ William Jul 27, 2015 ]
You don't want tall unless you are standing during the listening! If you are sitting the stands should have the speakers at eye level! 15 to 24 inch at the most! Because of the size of 703s I purchased two center speaker stands that are about 16 inches high and 14 inches long to accommodate the large base! [ J. PATRICK Jun 17, 2017 ]
i have 36 inch stands i bought about ten years ago when i had the polk lsi9 speakers. several articles i've read over the years suggest 36 inch hight is a good fit for book shelf spkrs [ JAMES R Jun 16, 2017 ]
The best stand for LSIM 703 is 26-30 inches [ JOHN Jun 16, 2017 ]
If you have a good amp putting out 50 watts it should sound fine but LsiM line of loud speakers likes alot of power, mines are running with 135 watts and sound great. Hope this helps. [ John Dec 31, 2016 ]
I am running them at 100 watts each and they seem to take a little more to push them than my older Polk speakers. I think they would sound okay (these things are amazing), but would probably not sound up to their potential. [ David Dec 31, 2016 ]
Minimum recommend power is 20 W. Not an expert but I imagine that they will sound great at lower volume levels. A problem with any underpowered amp is clipping. When you try to listen to something at high volume the amp won't be able to deliver and you end up sending a clipped signal to your speakers which can damage them. I've heard it's better to have an amp that exceeds your speakers max rated voltage (headroom) than to under power them if you like loud music [ chris Dec 31, 2016 ]
with the power mentioned i'm thinking the listening area is small. i think 50 watts will work out fine. i have four lsim 703s and a lsi center i use in a 5.1 setup. for music i don't turn up the volume that high. i'm using a sony ZA3000es AVR that is rated at 100 watts per channel [ JAMES R Dec 30, 2016 ]
50 watts is not adequate for this speaker because its sensitivity is 88dBs! I am pushing it with a Parasound amp that is rated at 125 watts RMS! I would think that 100 watts is minimum! Look for two way with higher sensitivity and lower watt handling max. [ J. PATRICK Dec 30, 2016 ]
1 answer I'm considering matching a pair of Polk LSiM 703's with either a Marantz PM 6006 or Cambridge CXA60 amplifier. Does anyone have any thoughts or experience on how this combination might work? I live in the wilderness and have no nearby dealers to test the equipment in person. Thank you! [ Brad Nov 11, 2016 ]
Hello, I actually had the Marantz PM6005 & PM6006 in my home prior to finally purchasing the Cambridge. I really enjoy the Marantz and their warmth. I also own the older PM7000 and use it on a second system. However, the Cambridge CXA60 was a huge surprise. This amplifier IMO punches a bit above its rating and I feel like both the other Marantz models are a bit too laid back for my liking. I found myself needing to constantly adjust the volume, and direct controls on the Marantz. This was not an issue with the Cambridge CXA60. The sound is warm but not overly so. I feel like their new pieces are great matches for a wider variety of speakers, whereas the Marantz stuff does require a bit more "pairing" attention. It broke my heart to send back a Marantz for a shot in the dark on this Cambridge but man I'm glad I did! If I didn't already own a cd transport that I was very happy with i would have purchased the Cambridge transport as a partner to the CXA60 also. I cannot recommend the CXA60 enough! I hope this helps. Pros - Warm sound across the board Great design and looks High quality components Nice weighty remote with very basic controls, also compatible w/other Cambridge pieces Seems more powerful than its rating suggests Cons - Not exactly a "budget" price but I feel it's well worth it Again, hope this helps. Cheers! [ Derek Nov 11, 2016 ]