Computer Audio Design’s GC1 Ground Control was created to tackle high frequency noise reduction at the level of the signal ground plane. Now, designer Scott Berry is launching an upgraded version, the GC1.1. How does it compare?
“The impact on sound quality is more significant than you might anticipate,” says Berry, of the result of tackling high frequency noise in this ground-breaking way. “Allowing customers to hear a Ground Control is our best sales technique.”
Over the past decade, the amount of high frequency noise on our mains power has increased dramatically due to the use of computers, routers, modems, WiFi and switch mode power supplies, etc. At the same time, the high frequency noise that is generated within our audio systems has also increased, largely through greater use of digital components.
Berry believes that this high frequency noise, while in itself inaudible, is so damaging that it changes the very ‘personality’ of sound. To get to the bottom of it, he – unlike most audio engineers – opted to target the signal ground plane, having discovered that all is not as it may seem on that plane.
In an audio system there are two independent voltage reference points: earth and signal ground. Signal ground is a point to which all signals within the device are referenced, and is the “negative” side of an electrical connector – whether RCA, XLR, USB, etc. So when you measure, say, a component’s signal/noise ratio, dividing the maximum output of a device by its minimum output, the reference point for both measurements is signal ground. But if the ground plane has noise on it, then such specifications can be misleading.
“Most people imagine that signal ground is a nice, flat uncontaminated thing that we call ‘reference’,” explains Berry. ‘But in reality this is far from true. Signal ground is contaminated. It is full of high frequency noise. It is my belief that reducing high frequency noise on the signal ground plane is a key factor in ensuring the clearest possible sonic platform for a hi-fi system.”
Like the original GC1, the new GC1.1 Ground Control’s methods for cleaning up high frequency noise are something of a closely guarded secret, but involve a highly complex combination of proprietary materials, borrowing technology from aerospace engineering and featuring an ultra-precise internal configuration and construction. The challenge, reports Berry, is the fact that noise in everyone’s system is different, operating in varying frequency bands. The materials brought together in the GC1.1 therefore had to effectively tackle a broad frequency spectrum. Considerable attention is paid to the GC cables and connectors, since it is essential that the route from signal ground into the Ground Control is the easiest one that the high frequency noise can take.
The GC1.1 Ground Control can be connected to any audio component that has an unused input or output connection. Whether a DAC, streamer, computer, CD player, NAS, router, phono stage or preamplifier, etcetera – if it has a spare input or output connector (RCA, XLR, spade, USB or Ethernet) then you can plug in the GC1.1 Ground Control.
The CG1.1 Ground Control is available now, priced at £1,995 in the UK, and $2,250 in the US. Cables are priced separately, at £300 and US$350.