CAD - Computer Audio Design

GC1 Ground Control

CAD believes that one of the key reasons so many digital audio products “sound digital” is due to high frequency noise. From the very beginning of CAD we have worked hard to reduce unwanted noise in all our products. Materials and technologies that are used in our 1543 MKII DAC , USB Cables and CAT are included in the GC1 Ground Control.  Over the past 15+ years the amount of high frequency noise on our Mains power has increased dramatically due to the use of computers, routers, modems, wifi, switch mode power supplies, etc.  The high frequency noise that is generated within our audio systems has also increased:  DACs, Servers, Computers, NAS drives, Routers, WiFi, etc. are all connected directly to our audio systems.

The Ground Control contains a mixture of materials that converts high frequency energy into heat.  Our research has found that to achieve the best sound quality the GC1 needed to be effective over a large frequency range. This was not easy to accomplish!  The GC1 will substantially reduce noise from very high KHz range up to over 15 GHz.

There are two independent voltage references in an audio system:

1) Signal Ground
2) Earth

Earth is what the third pin on your mains plug is connected to and what your copper pipes in your house are connected to. Earth is not typically (but occasionally is) connected to the Signal Ground in higher quality audio components.

Signal Ground is the negative side of an RCA, XLR, USB etc. connector.

Most audio engineers put a lot of effort into making sure the positive and negative rails of their DC power supplies have low ripple and noise, adequate bandwidth, etc. but typically not much thought is put into the signal ground plane.

CAD believes that reducing high frequency noise on Signal Ground and Earth improves sound quality.

Unfortunately there isn’t a common industry accepted technique for measuring noise levels on Signal Ground or Earth. A common measurement is Signal to Noise (S/N) ratio. S/N is the maximum output of a device (0dB) divided by the minimum output of a device (the noise). The reference for both of these measurements is Signal Ground. S/N measurement is not the whole story because it does not tell you anything about noise on the Signal Ground. You can have a very good S/N measurement and in reality the system can have considerable noise on the Ground side.

The CAD GC1 Ground Control can be connected to any audio product that has an unused output or input connection. If your DAC, streamer, computer, phone stage, preamplifier, amplifier, CD Player, NAS, etc. has a spare output/input connector like an RCA, XLR, Spade, USB or BNC you can connect the GC1 Ground Control to that. We supply a range of interconnects with various connectors. The other end of the interconnect has a single 4mm banana plug that attaches to the GC1 Ground Control.

There are two connectors on the back on the GC1 that allow you to connect two components, or use both connectors for a single component, or daisy chain more than one GC1 together.

The GC1 Ground Control can also be attached to Earth. If you have any type of Earth connection on your audio system or power distribution CAD can supply you a cable with an appropriate connector that will fit.

We typically get the best results connecting the GC1 Ground Control to the device in your system that has the highest noise levels:  components like computers, audio servers, DACs, CD players, NAS, routers etc. or by connecting the GC1 Ground Control to mains Earth.  These are the best places to first try connecting the GC1 to.

Sound quality improvements that we feel occur with the GC1 Ground Control are:

• Dynamics
• Timing
• Soundstage becomes wider and deeper
• Tonally more correct – voice and instruments sound more realistic
• Blacker background – less noise




Dimensions are:  322 (L) x 111 (W) x 88 (H) mm

Weight :  4.65 Kg

The GC1 Ground Control can be demonstrated at any of our dealers.  Please contact CAD directly if you do not have a dealer in your area:

+44 (0) 203 397 0334