Reference Performance USB Cable With Battery Power Supply And Active “Regenerate And Revive” Circuit

In 2013, Light Harmonic launched the world’s first ultra-wide bandwidth USB cable, LightSpeed 10G USB. Users and reviewers said LightSpeed 10G simply got the musicality, tone, detail, timing, everything right.  Many of these people didn’t believe that a USB cable could possibly make such a big change until they heard it for themselves!

Now we’re back for another assault on the limits of USB Audio performance with our new LightSpeed 20G USB cable.

With our new LightSpeed 20G USB Cable we enhance two key things: (1) Completely bypass the USB sending device’s noisy 5V power supply with an ultra low noise 5V battery based power supply (2) Regenerate and re-clock the USB high speed data stream with our “Regenerate and Revive” circuitry that exceeds the USB 3.0 standard.

These advances allow us to completely eliminate what we feel are the two largest problems with USB transmission for high-resolution audio: power supply noise pollution, and data stream timing errors.

Full 20G bandwidth (10 Gbps up and 10 Gbps down) is achieved by seamlessly integrating our “Regenerate and Revive” circuitry with the 10G LightSpeed USB cable. No insertion loss, no impedance mismatches from unnecessary connection points, just the best possible USB connection between your source and DAC.

Understanding Our Roots:

Before we go into more detail about 20G, here’s what people have said about our stellar LightSpeed 10G cable:

I heard an extended frequency response at both ends of the spectrum; more air and apparent detail on high strings and cymbals, deeper more powerful bass that gave drums terrific kick and snap. Never did music sound bright, edgy or hyper  detailed. Big, clean, clear, natural and exciting were words that frequently came to mind.

A Soundstage to Die For…

Using the LightSpeed provided an enormous soundstage that just about matched what I was hearing with the subwoofer in the system. The depth and width were excellent with lateral reproduction of instruments that went well beyond the outer border of the speakers.

A thousand dollar USB cable probably won’t be set to work with a thousand dollar DAC. You’d be better off buying a two thousand dollar DAC. However, if you’ve got a $5kish decoder, the LightSpeed is well worth a look. I’ve now got it running direct out of a MacMini and into Resonessence Labs’ flagship INVICTA Mirus. Does it bring improvements? Yessir

Light Harmonic LightSpeed is a different USB “beast.” It’s packed different, it’s designed different, it looks different and it performs on different level.

Continuing To Innovate

LightSpeed 10G is an excellent cable, and we took our time in designing the LightSpeed 20G to ensure that we were building a product that could consistently outperform our previous reference design.

It all starts by eliminating the 5V DC electrical connection between the source device and DAC. By replacing the inbound USB power with the LightSpeed 20G’s tightly regulated battery supply, we ensure that your USB DAC enjoys the cleanest, most stable power available during the initial handshake, without introducing the potential of ground-plane noise or electrical interference from your source device’s power supply.

Even though your DAC doesn’t draw power from this USB 5V supply after the initial handshake, it’s a primary source of noise in USB audio.

Not Just Ones And Zeroes

Next, we tackle the toughest part- how to deliver bit-perfect wide bandwidth data over the USB bus.

Many people don’t realize that USB data isn’t simply a string of ones and zeros passing over a cable- due to the extremely large data throughput required, the USB standard requires that data be bundled up and sent in bursts. Each burst is contained inside a roughly ellipse-shaped envelope which can be seen on test equipment as an “eye pattern”

While the leading and trailing edges of this eye pattern are precisely tapered (giving it its eye shape), the top and bottom of the “eye” must be flat. It is the goal of any USB send/receive link to pass this eye pattern through the circuit exactly as originally generated with all data inside the envelope perfectly preserved.

Signal loss caused by poor high frequency performance, inadequate shielding, or variations in cable impedance can cause this eye pattern to becomes distorted which in turn causes dropouts and timing errors in the received signal, or in extreme cases no signal at all!

While our cable is an extremely wide bandwidth design cable of passing over 10 Gbps in both the send and receive directions simultaneously, great cable geometry can only do so much if the original data stream is compromised at the source.

By completely regenerating and re-clocking the USB data signal inches from the computer’s USB port, LightSpeed 20G is able to improve upon the performance of many computer’s USB sending chipsets and deliver a near perfect data stream to your USB DAC. The audible differences are not subtle, and unlike many other flagship USB cables, the differences are backed by solid engineering

A Word On Timing

With LightSpeed 20G, we not only regenerate the USB data stream, we completely reclock it using an extremely precise femto-grade crystal oscillator. This extremely high-precision clock makes sure that the reconstructed USB data stream is presented to your DAC with absolutely no digital timing errors.

We at Light Harmonic feel strongly that we have designed the best performing USB cable available by combining the design and materials strengths of our LightSpeed 10G cables with active circuitry designed to eliminate power supply noise, completely regenerate the USB data stream and present your DAC with a perfect USB data stream.

If you already own a LightSpeed USB cable, or another quality audiophile USB cable, we welcome you to audition our newly- launched LightSpeed Revive, which contains the low noise USB battery supply and USB 3.0 compliant “Regenerate and Revive” circuitry found in LightSpeed 20G for use with your existing cables.


Q: How do I turn the LightSpeed 20G’s 5V power supply on and off?

A: LightSpeed 20G’s power supply is a smart, signal sensing design that powers up in the presence of USB data, and will trun off after a period of inactivity


Q: How much listening time will I get between charges?

A: LightSpeed 20G’s 3100 mAH battery has enough internal charge to last for hundreds of hours of normal use. For 24/7 operation though, simply connect a low noise power supply (from a Pulse LPS or other device) to the the LightSpeed 20G’s standard micro USB “B” charging port, and never worry about the battery’s charge state.