This is the pinnacle of home audio performance. It’s the place where recorded sources are accurately revealed, where their true dynamic qualities are fully experienced. It’s the place where movies reach off the screen and envelope you. This is the reason we got into this business in the first place: to ignite your entertainment with realistic audio impact, lifelike details and deep bass thrills. Hear over 40 years of audio passion in today’s LSiM Series.

Serious Sound, Serious Fun

We designed the new LSiM Series to produce the sound we wanted to hear: that natural, clear, deeply engaging “classic” Polk sound. To do it, we completely reengineered transducers, developed new materials, conceived new structures, incorporated patented and proprietary technologies.

The result is a pair of loudspeakers that delivers an astonishingly bold, totally realistic listening experience. They are effortlessly capable of believable imaging with pinpoint details; wide, enveloping midrange and deep, musical low-end response.

The LSiM Series of high performance loudspeakers is an audacious reimagining of the Polk mission of making superior audio accessible to everyone. Even though these loudspeakers straddle the very sharpest cutting edge today’s technologies, and feature custom-designed components and furniture-grade wood enclosures, they remain surprisingly affordable (and immensely engaging).

LSiM is ultra-high performance audio for today’s high-definition media.

Technology & Features

Dynamic Sonic Engine (Driver & Tweeter)

This is a molded enclosure within the cabinet that houses the super-accurate ring radiator tweeter and the extended motion midrange driver in their own separate, tuned compartments. This aligned, optimized array contributes to wide, uniform dispersion in the critical 200Hz - 2kHz range. The dynamic sonic engine, in turn, lives in a separate, rigidly braced enclosure-within-the-enclosure. This separation and specialized tuning measurably reduces performance-robbing back wave reflections. The result is astonishing detail and realistic imaging, with improved transient response, exact timbre-matching, and greater horizontal off-axis response.

Enhanced Ring Radiator Tweeter

Our engineers took the ring radiator tweeter, usually seen in only the most exotic speakers, and found way to improve it. They reshaped the tweeter’s bullet-shaped phase plug to eliminate horn-loading and improve dispersion. Redesigning the tweeter faceplate and the diaphragm added efficiency. Finally, they gave their new ring radiator tweeter its own tuned enclosure within the dynamic sonic engine. This enhanced ring radiator boasts higher power handling, extended dynamic range, better dispersion and extended top-end response.

Cassini Oval Subwoofer Drivers

Our newly designed subwoofers incorporate Cassini ovals cones to increase surface area without adding width to the cabinet for deeper, more musical low frequency response and dramatically improved imaging. Overhung voice coil designs allow larger excursions and higher power handling. Bass is deep, and blending is smooth.

Klippel Optimized Dynamic Balance® Transducers

All transducers are developed using our proprietary Dynamic Balance technology to reduce or eliminate unwanted material and interface resonance that color the sound. Klippel measurement systems are employed during development to ensure the speaker will deliver life-like highly detailed playback at both low and high volumes levels.

Super Cell Aerated Polypropylene Cone Material

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 and our super cell aerated polypropylene cone material is about as perfect as it gets. It’s the ideal balance of lightweight stiffness with high damping, along with good resistance to moisture, UV and temperature extremes. Our drivers are fast, linear and nearly resonance free.

Butyl Rubber Surrounds

Durable, soft, injection molded butyl rubber surrounds are computer modeled to absorb and suppress unwanted cone resonances. Our new rubber material is impervious to UV, extreme temps and humidity, for a lifetime of smooth, reliable sound.

Extended Linear Motion (ELM) Voice Coils

Allowing lots of movement in a limited space, ELM voice coils power the LSiM midrange and mid-woofer drivers to extend their higher frequency response with much less impedance. (LSiM subwoofers use overhung coils, which allow the larger excursions and greater power handling necessary for big subwoofer performance.)

Cast Aluminum Baskets

These lightweight, splayed strut design baskets provide a rigid structure for precise alignment of the speaker’s active parts, for flat response and low distortion, with no mechanical resonances or ringing. The open design provides ample venting for unobstructed linear movement.

Orth Crossovers

Proprietary engineering, designed and patented by Polk to maintain a lower order crossover design and increase power handling. Orth crossovers feature mylar and polypropylene capacitors for sparkling highs and air core inductors for superior transparency. Notch filters and sophisticated Zobel circuits smooth the impedance curve of the system for more efficiency and better high frequency response.

The LSiM Enclosure

The enclosure is an integral part of the sound design of the new LSiM Series. All LSiM cabinets are made of 1.0" MDF on the sides, 3/4" on the back and bottom, and wide radius baffles of robust 1 1/4-inch MDF. Substantial internal cabinetry, each driver with its own separate asymmetrical chamber, increases efficiency and banishes internal resonances and standing waves, for high power handling and incredible smoothness. The narrow baffle with its wide radiuses enhances the imaging for a very wide, deep and well-defined soundstage.

Zero-Diffraction Magnetic Grilles

Super thin 1mm, zero-diffraction grilles have been exhaustively tested and have no measurable effect on the speaker’s response. Completely unobtrusive, stylishly sheer, these grilles lock in place magnetically.

PowerPort® Bass Venting

PowerPort bass venting technology uses a specially designed port tubes and a uniquely shaped “kiss” at the mouth of the bass port to direct moving air as it exits the port, promoting “laminar” airflow by gradually normalizing the pressure to that of the listening room. The lack of turbulence means no wasted power, low distortion and no port noise, resulting in more efficient and impactful bass response.

Timbre-Matched Series

The LSiM main, center and surround loudspeakers are timbre-matched for a seamless speaker to speaker blend, so vital for achieving the incredible realism and enveloping surround effects found in the best multi-channel systems.

Dual Metal Gold-Plated 5-Way Binding Posts

Five-way Gold-plated Binding Posts provide the most professional, secure connections.

Bi-Amp or Bi-Wire Capability

For the ultimate in high performance, customized audio the LSIM Series has both bi-amp and bi-wire capability.

Innovative Hex-Head Floor Spikes

Our unique designs allows you to precisely level your towers without having to tip them—a big deal if you’ve ever tried that.

Rubber Trim Finishes

Beautiful furniture-grade fit and finish, with no visible screws.