{"title":"Computer Audio Design","description":"Dedicated to achieving the finest sound quality from computer audio sources. Computer Audio Design products should be at the heart of any audiophiles audio system.  Their single-minded products produce stunning realistic music and audio reproduction.","products":[{"product_id":"cad-ground-control-gc1","title":"CAD Ground Control GC1","description":"CAD GC1 \u003cbr\u003e\u003cbr\u003e\n\n\n\nComputer Audio Design is a small London based company with a quest to get the best possible sound out of digital audio. Designer Scott Berry is a hair shirt sporting purist, a state of affairs made explicit by his 1543 MkII DAC which has only one input and one pair of outputs (USB and RCA respectively), the mains cable is a heavyweight, inflexible affair that is captive – you cannot disconnect it from the DAC – and the case is made entirely out of acrylic. As a result the CAD is among the most natural, effortless sounding digital to analogue converters on the planet. But that’s not enough for Scott, he realises that the enemy of high resolution is noise, not the cars driving by outside but noise coming from the mains and from other audio components. He’s right, the less noise there is floating around a system the quieter the background to the sound and the more you can hear, it’s what differentiates the great from the good in all forms of electronics.\u003cbr\u003e\u003cbr\u003e\n\nYet we live in a world where the power coming out of the wall is increasingly polluted by noise from all manner of sources. Some try to combat this problem with mains filters and regenerators and these help but usually have limitations when it comes to getting enough amperage to power amplifiers. But the Ground Control is different, it doesn’t sit between the mains and the audio hardware, it plugs into the hardware or the mains and absorbs noise, it is essentially a passive device, hence the lack of illumination. Scott explains that the Ground Control contains “materials that convert high frequency energy into heat” for that is where the problem lies in his view. It comes from the switch mode power supplies in computers, routers, NAS drives etc and is the main reason why linear power supplies make the devices they power sound better, even if that device is a broadband switch that should have no bearing on the sound. It’s the noise that it adds to the signal that degrades the sound. Quite how the GC1 achieves this is a well kept secret but what Scott will say is that it works over a very wide band “from very high kHz range to over 15GHz”. Noise that’s well out of the audio band yet when you reduce it the effect is not at all subtle. \u003cbr\u003e\u003cbr\u003e\n\nThe GC1 absorbs both noise on the signal ground that exists within components and is carried by the negative side of an any audio connector between components, and noise on the earth as found on the earth pin of a mains plug and connected directly to the majority of components. So there is plenty of scope for this noise to get around a system.\u003cbr\u003e\u003cbr\u003e\n\nThe GC1 can be connected with up to two individual components with cables that terminate in a number of connections including USB, 4mm banana plug, RCA plug etc. Or it can be plugged directly into the mains with a connector that has two banana plugs for the GC1 and a 13A plug at the other end. In my system the latter approach produced the biggest improvement, presumably because it reduces noise for the whole system, a system that has more than two active components. But one of the first things I tried it on was a Tom Evans Groove Anniversary phono stage, another acrylic encased piece of kit, and my Townshend Allegri passive preamplifier. In this situation it increased low level resolution and made the quieter elements in the music easier to appreciate, it also improved timing, a quality that I place very high in the pantheon of audio essentials. Latterly I tried the GC1 on the Allegri alone and was surprised to find it remained beneficial, the explanation lies in the fact that there is noise coming out of connected components and the Allegri passes it on to the power amp to be amplified. In fact when I disconnected the phono stage the result remained almost the same, vinyl of course being an unlikely source of high frequency noise. Reconnecting the earth point on the Groove did have its benefits however, it is connected to the mains after all. This time notes gained depth and solidity, and timing did what I wanted it to do; got more coherent.\u003cbr\u003e\u003cbr\u003e\n\nUsed with CAD’s 1543 MkII DAC, a device that contains the same materials as the GC1 in order to make it as electrically quiet as possible, the realism went up a notch or two. Taking it away to check that I wasn’t just imagining it the sound lost its focus, so back it went and with it came a freshness of tempo and musical flow that was previously masked by what little noise there is coming out of this DAC. It does remarkable things for reverb, transforming the drum sound on ZZ Top’s ‘La Grange’ and revealing precisely what the two guitars are doing during the ‘solo’.\u003cbr\u003e\u003cbr\u003e\n\nWith a less fanatically constructed converter, a Primare DAC30, the noise floor dropped audibly and there was more shine, clarity and purity to the sound overall. Another DAC, the Bryston BDA 3, opened up low level detail and produced much cleaner highs, and yes timing improved as well. A potential source of noise in most streaming systems is the NAS drive, a computer peripheral that has not been designed with sound quality in mind yet provides relatively affordable storage for music files. I use something that was designed for sound quality, a Melco N1A server, which has a linear power supply and effectively means you don’t need a gigabit switch at all, but it too improved markedly when I hooked up the GC1. The sound opened up and gained in vitality with a more fluent and yet calm delivery that lost much of the glare associated with digital sources.\u003cbr\u003e\u003cbr\u003e\n\nThe Ground Control effect is that you end up with a system that can be played at higher levels without discomfort because distortion and noise has been significantly reduced. It’s a win win state of affairs that is so dramatic that you wonder why no one has done it before. Presumably the materials themselves are new but likewise the problems that they address have become far more prevalent in the digital age. Switch mode power supplies have only become common place in the last twenty years and broadband networks are pretty new as well. Technological advances bring their own problems and those of us with decent sound systems are more likely than most to suffer them, so disconnect those homeplugs forthwith, kill the wi-fi and turn off the fridge. If that sounds too drastic invest in one or more of these innocuous black boxes and be amazed. The GC1 is nicely built and finished but still seems expensive for a passive device, yet I would challenge anyone to produce as great an improvement in a serious system with anything more affordable.\u003cbr\u003e\u003cbr\u003e\n\nSpecifications:-\u003cbr\u003e\nDimensions DxHxW: 322 x 88 x 111mm \u003cbr\u003e\nWeight: 4.65 kg\u003cbr\u003e\n","brand":"Computer Audio Design","offers":[{"title":"Default Title","offer_id":57413353341260,"sku":"CADGC1","price":1412.5,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1053\/6891\/2204\/files\/CAD-GC1.jpg?v=1777542474"},{"product_id":"cad-ground-control-gc3","title":"CAD Ground Control GC3","description":"Less noise, more music: Computer Audio Design (CAD)\nintroduces new GC3 Ground Control, three times the size\nof the original GC1\u003cbr\u003e\u003cbr\u003e\n\nThe new GC3 is built on identical principles but, as the name suggests, is three times the\nsize.\u003cbr\u003e\u003cbr\u003e\n\nCAD’s GC1 and GC3 Ground Controls are specifically designed to target high frequency\nnoise on signal ground and mains earth, substantially reducing noise from the very high kHz\nrange up to over 10 GHz.\u003cbr\u003e\u003cbr\u003e\n\nThe Ground Controls provide an effective sink for high frequency noise, which is absorbed\nand converted to heat, resulting in a reduction of noise in your audio components. Their\nmethods of doing so borrow technology from the aerospace and telecoms industries,\ncombining proprietary materials in an ultra-precise internal construction. Considerable\nattention has equally been given to the GC cables and connectors in order to maximize the\nabsorption of high frequency noise.\u003cbr\u003e\u003cbr\u003e\n\nCAD’s Ground Controls can be connected to any audio component that has an unused input\nor output connection. Whether a DAC, streamer, computer, CD Player, NAS, router, phono\nstage, preamplifier, amplifier, etc – if it has a spare input or output connector (RCA, XLR,\nspade, USB or Ethernet) then you can plug in the Ground Controls whose sleek, hyperminimalist\ndesign will fit discreetly into your system.\u003cbr\u003e\u003cbr\u003e\n\nLike the GC1, the GC3 can also be connected to mains earth, the results of which can be\nbreathtaking. While the GC1 has two connectors – allowing you to hook up two components,\nto use both connectors for a single component or to daisy chain more than one GC1 to a\nsingle component – the GC3 sports six, allowing multiple components to form a common\n‘star’ earth connection.\u003cbr\u003e\u003cbr\u003e\n\nAn obvious upgrade\u003cbr\u003e\n“The benefits are more obvious than you might think,” says Berry, who enjoys nothing more\nthan watching jaws drop at the audible difference in sound quality. “You’ll certainly hear a\ndifference,” he ventures, “but the degree of difference will depend on how you use the Ground\nControls in your system.” Experience has shown that the best results are often achieved by\nconnecting a Ground Control to the noisiest device in your system – typically a digital\ncomponent. But the possibilities are many and varied, which is why Berry actively encourages\nexperimentation.\u003cbr\u003e\u003cbr\u003e\n\nThe impact can be a significant drop in the noise floor, which means that every element of the\nmusical performance can reveal so much more. Expect liberated dynamics and a sharpening\nof pace, rhythm and timing. The soundstage becomes both wider and deeper, with a natural\nsense of presence. Toning is more truthful, such that voices and instruments become more\ndistinct and authentic. And of course the background silence is that much more silent,\nenabling far greater separation, clarity, colour and texture.\u003cbr\u003e\u003cbr\u003e\n\nGC3 Dimensions: 458mm (w) x 356 mm (d) x 89mm (h)\u003cbr\u003e\nWeight: 16 kg","brand":"Computer Audio Design","offers":[{"title":"Default Title","offer_id":57413353374028,"sku":"CADGC3","price":3329.17,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1053\/6891\/2204\/files\/CAD-GC3.jpg?v=1777542478"},{"product_id":"cad-usb-cable","title":"CAD USB Cable","description":"The CAD Audio USB Cables\u003cbr\u003e\u003cbr\u003e\n\n \nThe CAD Audio USB Cables are optimised specifically for audio use in conjunction with a USB Digital to Analogue Converter.\u003cbr\u003e\u003cbr\u003e\n\nCompared to purely analogue devices (e.g. turntables), digital audio source components produce more high frequency “noise” (EMI\/RFI). This is generated within CPUs, chipsets, switch mode power supplies and regulators and so on. Also the basic USB carrier frequency can be in the 200 MHz to 400MHz frequency range. Digital audio interconnects have a range of issues that are significantly different from analogue audio interconnects. During listening tests we found that when we reduced the amount of this “noise” from reaching the Digital to Analogue Converter (DAC), sound quality dramatically improved in our opinion.\u003cbr\u003e\u003cbr\u003e\n\nSecondly, it is now widely accepted that the materials and construction of analogue cables can influence the quality of sound that a system produces, and our thesis (which again, is now more widely accepted) is that digital cabling has at least the same impact.\u003cbr\u003e\u003cbr\u003e\n\nNoise reduction\u003cbr\u003e\u003cbr\u003e\n\nCAD Cables feature our patented USB filter, which filters noise from the music source (whether a computer or audio server or streamer).\u003cbr\u003e\u003cbr\u003e\n\nThe USB consists of 4 connections:\u003cbr\u003e\n\n1) +5V : Only used for powering devices – many DACs use this power source, but not all.\u003cbr\u003e\n\n2) DATA+ : Differential signal, very high speed\u003cbr\u003e\n\n3) DATA- : Differential signal, very high speed\u003cbr\u003e\n\n4) Ground : Reference\u003cbr\u003e\u003cbr\u003e\n\nUnwanted noise is present on all 4 connections. Our patented filter reduces the noise on the differential signal. +5V and Ground without damaging the signal or power itself.\u003cbr\u003e\u003cbr\u003e\n\nThe +5V line contains exceptionally large amounts of high frequency noise. To minimize the amount of this noise from entering the DATA and Ground connections, the CAD Cable uses a separate highly shielded cable for the +5V line.\u003cbr\u003e\u003cbr\u003e\n\nWire materials and construction\u003cbr\u003e\u003cbr\u003e\n\nCAD sees “Digital Signals” as very high speed analogue square waves. Conductors used for high speed signals use different materials and construction techniques compared to conductors that only operate at lower frequencies. As explained above there are 4 conductors in a USB cable. The requirements for the DATA+ and DATA- conductors are completely different from those for the Ground and +5V conductors.\u003cbr\u003e\u003cbr\u003e\n\nWhen we compared conductors made with different materials and\/or construction techniques we also noted sound quality differences. We have meticulously researched the best materials and construction techniques for the conductors inside our CAD cable. Our main measurement tool is subjective listening tests, but over time we learned what parameters are technically important.\n","brand":"Computer Audio Design","offers":[{"title":"I","offer_id":57413353570636,"sku":"CADUSBCABLEI","price":541.67,"currency_code":"GBP","in_stock":true},{"title":"II","offer_id":57422988607820,"sku":"CADUSBCABLEII","price":1041.67,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1053\/6891\/2204\/files\/CAD-USB-CABLE.jpg?v=1777542483"},{"product_id":"cad-ground-control-gc-r-gcr","title":"CAD Ground Control GC-R (GCR)","description":"The CAD GC-R Reference Ground Control\u003cbr\u003e\u003cbr\u003e\n\nOver the past 10+ 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.\u003cbr\u003e\u003cbr\u003e\n\nCAD believes that one of the key reasons so many digital audio products “sound digital” is due to this 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, GC3 and GC-R Ground Controls.\u003cbr\u003e\u003cbr\u003e\n\nThe 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, GC3 \u0026amp; GC-R needed to be effective over a large frequency range. This was not easy to accomplish! The CAD Ground Controls will substantially reduce noise from very high KHz range up to over 10 GHz.\n\u003cbr\u003e\u003cbr\u003e\nThere are two independent voltage references in any audio system:\u003cbr\u003e\n 1) Signal Ground\u003cbr\u003e\n 2) Earth\u003cbr\u003e\u003cbr\u003e\n\nEarth 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.\u003cbr\u003ev\n\nSignal Ground is the negative side of an RCA, XLR, USB etc. connector.\u003cbr\u003ev\n\nMost 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.\u003cbr\u003e\u003cbr\u003e\nCAD believes that reducing high frequency noise on Signal Ground and Earth improves sound quality.\u003cbr\u003e\u003cbr\u003e\n\nUnfortunately 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.\u003cbr\u003ev\n\nThe CAD GC1, GC3 \u0026amp; GC-R Ground Controls 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 connector has a single 4mm banana plug that attaches to the Ground Control.\n\u003cbr\u003e\u003cbr\u003e\nThere are two 4mm banana sockets on the back on the GC1 and six on the back of the GC3 and the GC-R.\u003cbr\u003e\u003cbr\u003e\n\nThe GC1, GC3 or GC-R 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. The outside case of any audio component that is made from metal by law must be connected to Earth for safety. So another option is to attach a Ground Control to the case directly by loosening a case screw and inserting a Ground Control cable with a spade connector.\u003cbr\u003e\u003cbr\u003e\n\nWe 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. The GC3 \u0026amp; GC-R work exceptionally well connected to your mains Earth connection and directly to the cases of your amplification.\u003cbr\u003e\u003cbr\u003e\n\nWe also have had very good results connecting a Ground Control to phono preamplifiers. The gain on these devices is large and the reduction of noise that the Ground Control provides has brought some amazing results.\u003cbr\u003e\u003cbr\u003e\n\nNote: Amplifiers\u003cbr\u003e\u003cbr\u003e\n\nWe do not recommend attaching Ground Controls to the output of audio amplifiers unless you completely understand the technical design, or the amplifier can be damaged\u003cbr\u003e\u003cbr\u003e\n\nOur results have shown that better sonic results are typically obtained by connecting Ground Controls to source components, preamplifier or an unused input of an amplifier.\u003cbr\u003e\u003cbr\u003e\n\nBut, if this is not possible and you wish to connect a Ground Control to the output of an amplifier (especially a balanced design) you must follow these rules:\u003cbr\u003e\n•Never connect a Ground Control to a positive output.\u003cbr\u003e\n•If you connect a Ground Control to the negative output NEVER connect the Ground Control to anything else. It is safe if you connect a Ground Control to the negative output of your amplifier only if the Ground Control is NOT connected to anything else.  If you also attached the Ground Control to another component or to Mains Earth you may short your amplifier and damage will result.\u003cbr\u003e\u003cbr\u003e\n\nWe are excited to announce that an interconnect company (that CAD really likes) called Bibacord is now making interconnects so that a Ground Control can be linked directly to the shield\/screen inside the cable.  In this arrangement you have a Ground Control connected to the screen\/shield along the entire length of the cable.  The reduction in high frequency noise in the interconnect produces what we feel is a more natural, larger sound stage with increased detail of an already amazing cable.\n","brand":"Computer Audio Design","offers":[{"title":"Default Title","offer_id":57415090209100,"sku":"CADGROUNDCONTROLGCR","price":16500.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1053\/6891\/2204\/files\/CAD-Ground-Control-GC-R.jpg?v=1777553759"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1053\/6891\/2204\/collections\/computer-audio-design-logo_dd571a4b-1906-416d-90e0-5bbe99116199.jpg?v=1777394260","url":"https:\/\/www.stoneaudio.co.uk\/collections\/computer-audio-design.oembed","provider":"Stone Audio","version":"1.0","type":"link"}