Polk Audio 900-LS
Our take on the Polk Audio 900-LS by Crutchfield's Marshall Chase
A real standout — but practically invisible
Polk's Vanishing® Series 900-LS in-ceiling speaker is designed to stay out of sight and out of mind...until you hear the rich, detailed sound it produces. This high-performance speaker hides away in your ceiling, which means you can enjoy great sound in rooms where regular free-standing speakers are an awkward fit.
Advanced 3-way design
The secret to the 900-LS's compact cutout size lies in Polk's innovative "Cassini Oval" driver design, which positions an oval-shaped woofer at an angle behind the midrange and tweeter array, in a built-in dual-ported bandpass enclosure. The woofer's increased surface area and rigid cast basket combine for deep musical bass. This speaker also features Polk's own advanced version of the classic "ring radiator" tweeter for smooth, detailed highs, along with a 3-1/4" Dynamic Balance midrange driver, for accurate response across a wide frequency range.
A wall distance toggle switch lets you compensate for boominess due to installation near a side wall. You also get a tweeter attenuation switch to help you get balanced sound in rooms with lots of reflective surfaces.
Mix and match with Polk's free-standing LSi M speakers
Use a pair of 900-LS in-ceiling speakers to listen to music in the den, or add more for a great sounding home theater. Vanishing Series LS speakers are voice-matched to Polk's renowned free-standing LSi M speakers, so you can combine these in-ceiling speakers with in-walls or free-standing speakers and get harmonious results.
An optional in-ceiling bracket is recommended for installing the 900-LS speaker in a home with new construction.
- frequency response 40-29,000 Hz (-3dB)
- three-way speaker design includes:
- 3/4" ring radiator tweeter
- 3-1/4" Dynamic Balance® midrange speaker
- 6" x 9" Dynamic Balance woofer with Cassini Oval driver design
- dual-port bandpass enclosure for better bass response
- handles up to 150 watts
- sensitivity 90 dB
- 8-ohm impedance
- paintable Sheer-Grille for stealth installation
- cutout: 8-3/16" diameter
- mounting depth: 9-3/8"
- warranty: limited lifetime
- Our 60-day money-back guarantee
What's in the Box:
- In-ceiling speaker
- White metal grille
- Mounting template
- Owner's Manual
- "Fitting the Grille to the Wall" label (attached to bag)
- Online Registration Card
- Polk Audio product brochure
Features and Specs
|Quantity in Package||Single|
|Woofer Composition||Mineral-filled polypropylene|
|Power Range (Watts)||10-150|
|Connector Type||Spring posts|
Vanishing Series In-ceiling Speakers: The Polk Audio Vanishing Series in-ceiling loudspeakers feature a precision-engineered, minimally flanged design and Polk's exclusive Sheer-Grille, which protrudes only 7mm from its surroundings. Installing virtually flush in your ceiling, the Polk Audio Vanishing Series in-ceiling loudspeakers offer a one-cut, drop-in installation and rotating cam stabilizing system. The Vanishing LS series in-ceiling speakers are timbre-matched to Polk Audio's flagship LSi and LSiM series loudspeakers for seamless blending from speaker to speaker when you're building a speaker system.
Cassini-Oval Woofer: This Polk Audio Vanishing Series 900-LS in-ceiling surround loudspeaker employs a rear-mounted 6" x 9" Dynamic Balance mineral-filled polypropylene Cassini-Oval cone woofer, with rubber surround, for a smooth, consistent frequency response. The oval woofer is mounted at an angle in the enclosure, behind the midrange and tweeter, and ported out the front.
3-1/4" Midrange: The 900-LS has a 3-1/4" Dynamic Balance aerated polypropylene cone midrange. The aerated polypropylene cone is 20% lighter than conventional polypropylene, and 35% lighter than aluminum, to give you clear midrange and high efficiency. Polk Audio's patented Dynamic Balance technology eliminates unwanted resonances.
Ring Radiator Tweeter: The 900-LS employs a 3/4" Dynamic Balance ring radiator tweeter for detailed highs and superb imaging.
Wall Distance Toggle Switch: If you mount your in-ceiling loudspeakers closer than 2 feet from a side wall, the proximity of the surface can elevate the midbass response between 50 and 200Hz, causing a boomy sound. To compensate, the 900-LS is equipped with the Vanishing Wall Distance Toggle switch, located on the front panel. The filter adjusts the crossover to flatten the response, and tune out the boominess, without sacrificing the deep bass response of the speaker. The switch is labeled "Wall Dist." with two positions: in (<2') and out (>2')."
Reflective Room Compensation Control: The Reflective Room Compensation Switch, conveniently located on the front panel, allows you to digitally compensate for harsh reflective surfaces, such as smooth walls, glass windows, and hardwood floors. The filter doesn't merely reduce high frequencies, it simply cuts the level only in the 4-5kHz range where room acoustics most often interfere with performance. The switch is labeled "Room" with two positions: out (normal) and in (reflective).
Frequency Response: The overall frequency response of the in-ceiling loudspeaker is 28Hz to 33kHz, and the -3dB frequency response is 40 to 29kHz.
Sheer-Grille: The 900-LS features Polk Audio's exclusive wafer-thin Sheer-Grille, a magnetically-secured metal grille that protrudes only 7mm from its surroundings. The Sheer-Grille can be painted to match your décor, making it virtually indistinguishable from its surroundings. The Sheer-Grille has nearly transparent, ultra-small perforations, and is acoustically inert, for dynamic, unimpeded sound and more uniform coverage, even in larger rooms. The grille diameter is 9-5/8.
Gold-Plated Spring-Loaded Posts: The in-ceiling loudspeaker has a gold-plated pair of spring-loaded binding posts that can accept up to 12-gauge wire, single- or dual-banana plugs, or pin connectors.
Applications: The Polk Audio Vanishing Series 900-LS in-ceiling loudspeaker is designed to be used as part of a hidden two-channel stereo pair or in a 5.1- or 7.1-channel home theater configuration. At only 9-5/8" in diameter, the speaker makes a minimal visual impact.
Note: The speaker isn't recommended for installation in high-moisture locations.
Security Eyebolt: The speaker has an eyebolt attached to the speaker magnet. This eyebolt is designed to be used as an extra measure of installation security. The majority of the speaker weight should be supported from behind by attaching a wire or hook to the eyebolt and to the ceiling joists.
Rotating Cam System: The Polk Audio in-ceiling loudspeakers utilize a rotating cam system to ensure a secure, vibration-free installation. Each 900-LS has 4 rotating cams to hold the speaker in place. The cams can be tightened from the front panel with a Phillips-head screwdriver.
Installation: The 900-LS can be installed in new or existing construction:
- Existing Construction: In existing ceilings, use the included cardboard template for one-cut, drop-in simplicity. Achieve secure, vibration-free efficiency with a simple turn of Polk's Rotating Cam system (4 rotating cams).
- New Construction: The optional PB LC60i pre-construction brackets should be used for new-build or open-wall retro-fitting.
|Overall Dimensions (with grille)||Diameter = 9-5/8" |
|Cutout Dimensions||Diameter = 8-3/16"|
|Mounting Depth (behind 1/2" drywall)||Depth = 8-7/8"|
Our Product Research Team
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5 questions already asked
There's no "one-way" it has to be positioned. The speaker offers "wall distance" and "Reflective Room Compensation" controls to provide greater mounting flexibility. You may want to check out our in-wall/in-ceiling speaker placement guide in the Crutchfield Labs: http://www.crutchfield.com/learn/learningcenter/home/speakers/inwall_placement.html?search=speaker_placement I hope that helps. My Bio: http://www.crutchfield.com/Support/Bio.aspx?bio=5 [ Ryan Nov 10, 2016 ] Staff
The design of these speakers makes it not necessary to swivel the tweeters so they don't move. The speakers does have a wall distance and a reflective room compensation switch to help you fine tune the sound while getting good audio coverage. Feel free to call an advisor for a personal recommendation. HTH! --Crutchfield My Bio: http://www.crutchfield.com/Support/Bio.aspx?bio=101 [ Paul Oct 10, 2016 ] Staff
I am using 900-LS as all five speakers, including center channel, front and rear; all in ceiling. You do need a good receiver to drive these. I love them. Great sound; really happy with the decision. [ Sandeep Aug 18, 2015 ]
I have used wall mounted Polk speakers in our previous home. In our new home only ceiling mount speakers are functional because it is a townhouse. Wall mounted speakers give a better sound compared to ceiling mount. I could tell the difference immediately. If ceiling mount is all you can use I suggest the best available speakers be considered. Feel free to contact me at any time. [ douglas Aug 18, 2015 ]
I forwarded your question to an Advisor and they responded with the following: I would recommend pairing the Polk Audio 900-LS series speakers with the Yamaha RX-A3040. The Yamaha is a 9.2 channel home theater receiver; it outputs 150 watts per channel. It has a audiophile quality DAC built in, newest version of HDMI, 4k technology, and will even do the newest version of Dolby surround, Dolby Atmos. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy Sep 03, 2014 ] Staff