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Why a powerline filter?

Protection, Isolation and Performance Enhancement


Powerline filters remove impurities and artifacts from the alternating current (AC) that energizes your components. In addition, powerline filters protect your equipment from potentially damaging voltage surges.

Powerline filters are definitely not all the same. In fact, most are designed for computer applications and consequently do not satisfy the more stringent requirements peculiar to refined audio and audio/video use. In particular, most fail to provide the high current delivery needed for the accurate reproduction of dynamic peaks encountered in music and video soundtrack reproduction.

In contrast to these Inferior designs, Lightspeed Powerline filters satisfy the following performance criteria:

Protects connected components from the potentially damaging effects of voltage surges. Sensing circuitry monitors AC voltage levels and "clamps" excessive voltages thus preventing them from reaching and damaging your components.

Reduces pre-existing AC interference without adding any artifacts of its own. Even when compared to pure 60 Hz AC power available only under laboratory conditions (or 50 Hz where applicable), the ideal filter would not impose any performance restrictions at all. In fact, the increased component-to-component isolation offered by carefully engineered powerline filters will improve audio and audio/video system performance.

Improves performance in direct proportion to the level of powerline contamination. Lesser powerline filters have the same effect regardless of where they are used because they impose performance anomalies on any connected component.

Delivers current instantly. This is in sharp contrast to the time lag between current demand and current supply always exhibited by conventional powerline filters. (It is, in fact, their single most glaring fault.) Lightspeed Powerline filters do not impose any current delivery limitation or hesitation. In that respect, Lightspeed products are the most passive powerline filters available today.

The irony of alternating current

The same AC that powers all electronic components is also a hindrance to optimum performance. The simple fact is that AC power is not pure--it is contaminated by numerous and unavoidable sources of interference.


A mild case of blood poisoning will not stop a person from functioning but the accompanying low-grade fever will certainly prevent that person from performing at a high level. In an analogous way, sophisticated electronic components fed with contaminated AC power will still function but at a level far below their peak potential. Research scientists, engineers and computer professionals have known this for decades. That's why they protect and enhance the performance of their delicate and expensive equipment with devices providing AC power filtration that effectively removes powerline contaminants.


Today's sophisticated audio and video components can reproduce ever smaller aural and visual nuances. These performance levels usually depend on ideal laboratory conditions. Real world performance often falls far short of peak potential when these components are connected to a standard AC line with its inherent contaminants.

Powerline contaminants are many and varied. Unfortunately, they are also extremely common--in fact, almost ever-present.

Problem 1: Voltage Surges

Instantaneous voltage surges in the AC line, sometimes reach into thousands of volts. In worst cases, these spikes first destroy component power supplies and then cascade to burn out all major circuitry blocks. Repairing the resultant catastrophic damage is always difficult and usually economically foolish as repair costs often exceed the original purchase price.

Lesser surges, far more common, are particularly troublesome for audio and video components due to the almost universal use of integrated circuits (ICs) in critical circuit paths. Although ICs allow unparalleled design freedom and cost reduction, they are also more voltage sensitive than discrete components. The result? Very minor voltage disturbances, even powerline transients produced when a refrigerator compressor turns on or off, can cripple audio and video components.

Lowest level voltage surges appear as a near-continual "hash" in the powerline. Produced primarily by any running motor (air filter, hair dryer, etc.), this noise doesn't overtly damage components but wreaks absolute havoc on the sound quality of audio systems and on the clarity and sharpness of video images. Worst of all, powerline hash is virtually never-ending. Even if you're not running a motor in your household, rest assured that your neighbor (whether next door or blocks away) is!

Problem 2: RFI and EMI

We live in the age of wireless communication. Like most technological blessings, this one has an accompanying curse. Radio and microwave broadcasts literally engulf us. Our skies are jammed. In some areas, AM stations appear as background interference on audio systems and televisions. Cellular phone service "bleeds" through other transmissions. In short, signal interference is a major concern.

Your home AC line is not immune. In fact, RFI (radio frequency interference) often corrupts the AC current going to your sensitive components. Although not usually dangerous to your system's long term reliability, this interference constantly robs you of the performance potential you've paid for.

The situation is indeed bleak; AC line purity is getting worse as technology proliferates. Bluntly stated, if AC power were water, your home components would be drinking from a sewer!

Verifying the problems: A quick reality check

How important are the interferences we've described?

Many audio-and videophiles know that their systems perform much better late at night or in the early morning hours than during normal waking time. The reason is simple: Off-hour AC power is usually much less contaminated (though far from perfect!) simply because fewer hash-producing electrical devices are in use. RFI and EMI also decreases because fewer over-the-air broadcast links and other interference-generating devices are used. top



Lightspeed Powerline filters effectively block performance robbing AC contaminants from affecting your valued components . . . and do so with an important difference.

Traditional AC filtration is available in many formats--from $10 devices adequate for protecting your clock-radio to hideously expensive and complicated systems with all the charm and aesthetic appeal of welding equipment.

Despite immense differences in cost and size, previous filtration schemes share one commonality: the use of inductive coils to block ultra-high frequency (RFI and EMI) noise.

However, coils have a fundamental drawback when used to filter AC for an audio or audio/video system. They introduce an unavoidable time-lag when subjected to instantaneous high current demands common when power amplifiers attempt to reproduce high level musical transients. The sonic penalties of this time lag include smeared transients at all power levels and diminished crescendos that lack true speed and impact of live music. Video performance suffers from reduced shadow detail, particularly in fast moving scenes that rapidly vary from light to dark and back again.

Although the coil eventually "catches up," the damage is already done. Audio data is robbed of immediacy. Video images are less convincing and enveloping.

Lightspeed technology provides both protection and enhancement. Each Lightspeed Powerline Filter passes the power transmission (AC) line through a unique multi segmented "lossy transmission" mechanism composed of select magnetic materials. This mechanism maintains proper impedances while severely reducing the effects of RFI/EMI. The total lack of inductive coils, including isolation transformers, ensures full current delivery and uncompromised performance. top   

The LIGHTSPEED Performance Advantage



Lightspeed Powerline filters are unique in their ability to effectively block voltage spikes and RFI/EMI without the use of any inductive coils. In addition to preserving your investment by protecting your delicate circuitry, Lightspeed Powerline filters enhance system performance. Freed from a coil's leaden effects, Lightspeed meets moment-to-moment current demands without hesitation.

Audiophiles benefit from increased spaciousness, transient resolution and dynamic contrast. Videophiles enjoy more stable images, better color saturation and fewer noise-induced artifacts. Home theater aficionados enjoy improvements in every operating parameter. Lightspeed users report the following performance enhancements:

  • Improved musicality

  • Deeper and wider soundstaging

  • More precise focusing

  • Improved transient resolution

  • Greater dynamic contrast

  • Extended frequency response

  • Improved video clarity, sharpness and color saturation

  • Improved performance of electrostatic loudspeakers

 A Lightspeed Powerline filter is truly a necessary requirement for maximum system safety and enjoyment. top

LIGHTSPEED Powerline Filters: optimized for your system

All Lightspeed Powerline filters use quick acting Metal Oxide Varistors (MOVs) to provide a minimum of 35 joules energy clamping capability. This line-to-line rating extends to all three legs of the AC source ("hot," "neutral" and "ground"). It is the equivalent of over 4,000 amperes and provides protection for delicate components and unrestricted current delivery for optimal system performance.

In addition, all Lightspeed products drastically reduce any potentially negative component-to-component interactions by providing superb isolation between analog- and digital-dedicated AC outlets. (The CLS 9900 AMP, specifically designed for power amplifier conditioning only, has no digital outlets).

For added performance enhancement, the CLS 6600 ISO, the CLS 9600 ISO, the CLS 9900 AMP and the HT 1000 include Power Factor Correction circuitry to properly phase-align AC's voltage and current components for the most efficient utilization.

Note: 220 volt versions of all Lightspeed Powerline filters suitable for use in areas with AC current from 200V to 240V are available. Ask your dealer for details.

The Lightspeed Vibration Control Spikes have been specially engineered and machined to reduce the vibration induced sonic degradation to lightspeed from the environment.

Lightspeed Powerline filters-enhanced performance to increase your enjoyment. 


APPLICATION NOTE 1: Home theater systems

Increasingly, home theater involving Dolby Pro Logic TM has become an important addition to home audio entertainment. The same general installation rules apply. For example, a video disc player incorporates digital-to-analog (D/A) converters just as a CD player does and hence must be treated as a digital source. AC power should come from a powerline conditioner's dedicated digital outlet. Some outboard surround decoders, surround preamps and even surround receivers employ D/A conversion in their decoding and/or surround enhancement circuitry. Logically, these should also be treated as digital sources but practical experimentation may be necessary as the amount of digital noise produced can vary greatly from unit to unit. Ask your dealer for recommendations concerning your specific system.

The final decision on where to plug in a particular component should ALWAYS be based on listening! Try powering the component through both outlet types (analog and digital) in turn. If performance improves when powered through the isolated digital outlet, leave it there. If you hear little or no improvement, return it to the analog outlet. Of course, the ideal is to have each component with digital processing completely isolated via its own socket from all analog equipment. Aside from achieving the ultimate in digital isolation, powering components by spreading their current loads across numerous Lightspeed units will also increase AC filtration effectiveness.

Television monitors in particular are quite susceptible to digitally generated AC-borne interference. In extreme cases, the resulting video noise is clearly visible as streaking or "light bursts" on the screen. More usually, this noise results in a poorly defined picture with low color saturation.

In short, increased filtration results in cleaner audio and video. Lightspeed Powerline filters not only protect your system from the potentially disastrous effects of powerline surges but improve all performance parameters.

APPLICATION NOTE 2: Electrostatic Loudspeakers

Electrostatic loudspeakers, considered by many to be among the fastest and most detailed speaker designs available, require their own own power supply to charge the speaker diaphragm. The charged diaphragm acts as an antenna picking up RFI from the air and injecting it through the speaker power supply's AC cord into the house powerline. This contamination reaches every component and electrical device in the house via the AC main junction box. Audible results include confused imaging, brittle highs, thin bass and a shrunken sound stage.

The cure is to isolate your electrostatic loudspeakers from all other equipment with a dedicated Lightspeed.

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