Polk Audio - LSiM707 - Floorstanding Loudspeaker - Midnight Mahogany - EACH

LSiM707
The Ultimate Floorstanding Loudspeaker

• Separate chambers for the midrange and tweeter improve transient response and imaging
• Cassini oval subwoofer drivers have more surface area for superior low-frequency response
• Klippel motor optimization ensures smooth volume spectrum ends for uniform performance at all volumes
• Patented Dynamic Balance® technology eliminates resonance so you hear good sound instead of distortion
• Qty Included1
• Height50.81" (129.06 cm)
• Width9.5" (24.13 cm)
• Depth18.44" (46.84 cm)
• Weight99.2 lbs (45 kg)
• Mid-High Array Driver Enclosure TypeSealed
• Mid-High Array Driver Complement
• (1)  1" (2.54 cm) d (Round) Enhanced Ring Radiator - Tweeter
• (1)  3.25" (8.26 cm) d (Round) Super Cell Aerated Polypropylene - Midrange
• (1)  6.5" (16.51 cm) d (Round) Super Cell Aerated Polypropylene - Mid/Woofer
• (2)  6" (15.24 cm) h x 9" (22.86 cm) w (Oval) Cassini oval, Super Cell Aerated Polypropylene - Subwoofer
CROSSOVER

• TypeOrth Crossover Design
• Midrange/Woofer Crossover Frequency100 Hz
• Tweeter/Midrange Crossover Frequency3 Hz
Specifications
Power Range 20-300
Frequency Response 38-30k Hz
Sensitivity 88 dB
Impedance (Ohms) 8
Subwoofer Amp Power ---
Height (inches) 50-13/16
Width (inches) 10-1/4
Depth (inches) 20
Weight 99.2 lbs
Driver Technology

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.

4-Way Driver System: The Polk Audio LSiM series floor-standing loudspeaker employs a 4-way driver system for crisp, detailed highs; natural, lifelike midrange; accurate, dynamic midbass; & deep, rich bass. The floor-standing loudspeaker houses a 1" Dynamic Balance Enhanced Ring Radiator Tweeter, a 3.25" Dynamic Balance Super Cell Aerated Polypropylene cone midrange driver, a 6.5" Dynamic Balance Super Cell Aerated Polypropylene cone midbass woofer, & two 6"x9" Dynamic Balance Cassini Oval subwoofer drivers.

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.

Cassini Oval Subwoofer Drivers: The Polk Audio LSiM series floor-standing loudspeaker uses dual Cassini oval subwoofer drivers. The Oval woofer shape increases surface area for deeper, more musical low-frequency response, while allowing for a narrower baffle design. The overhung voice coil design allows larger excursions & higher power handling. As a result, the bass response is deep & blending is smooth.

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.

Enhanced 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. The LSiM subwoofer drivers use Overhung Voice Coils, which allow the larger excursions and greater power handling necessary for big subwoofer performance.

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 floor-standing 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: 3 kHz, 18 dB/oct
• Midrange/Midbass Crossover: 300 Hz, 12 dB/oct
• Midbass/Subwoofer Crossover: 100 Hz, 6 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 20Hz to 40kHz & the -3dB frequency response is 38Hz to 30kHz.

Enclosure Design

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 floor-standing 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, & midbass woofer are housed in a separate internal sealed enclosure from the ported enclosure which houses the two oval subwoofer drivers.
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.

Connections

Dual Gold-Plated Binding Posts: The floor-standing 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 floor-standing speaker's binding posts are color-coded (red/black) for easy identification between positive & negative.

Mounting Options

Placement: To enjoy the most realistic stereo image and lifelike sound, place the floor-standing 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.

Rubber Feet & Adjustable Floor Spikes: Rubber feet & adjustable floor spikes are included with the LSiM floor-standing loudspeakers to anchor & stabilize the speaker on any type of floor (carpet, tile, or hardwood).

• Spiked Feet: The floor-standing speaker includes 4 pre-installed adjustable spiked feet. These adjustable spiked feet allow you to tilt the speaker backwards or forward a tiny bit in order to optimize your listening area. Most floor-standing speakers are adjustable only from the bottom of the base & require you to tip the speaker over using two hands to access the floor spikes. The LSiM floor spikes are adjustable from the top of the base using the included 5mm hex (Allen) wrench.
• Rubber Feet: The floor-standing speaker's 4 pre-installed adjustable spiked feet come covered with rubber protection tips to protect your hardwood or tile floor. These rubber tips are removable.