The CAD Ethernet Control is a small inline filter from British specialist Computer Audio Design that tackles high-frequency noise on the network connection of your audio system. It plugs directly into your streamer, server or DAC, and works with streaming services as well as locally stored music. CAD introduced it in early 2024, and today it is part of a growing family of noise-control products from the brand.
CAD Ethernet Control: why network noise matters
More and more music reaches our systems over a network cable. That cable does not only carry data, though. It also brings in high-frequency noise from routers, switches, computers and their power supplies. CAD’s position is clear: reducing that noise in a hi-fi system audibly improves its sound quality.
The CAD Ethernet Control addresses noise on three levels: the differential Ethernet signals, the signal ground, and the Ethernet interface of the connected device. For this it uses CAD’s proprietary noise-reduction technology, which the company also applies in its Ground Control and USB Control products.
Galvanic isolation with custom transformers
At the heart of the CAD Ethernet Control are proprietary CAD transformers. They provide galvanic isolation between the network and your audio equipment and, according to CAD, reduce noise over a wider frequency range than standard Ethernet transformers do. The design draws on 14 years of experience with products such as the CAD 1543 DAC, the CAD Audio Transport and the brand’s USB cables.
No cable, just a plug
Installation is simple. The unit has an RJ45 socket on one side and a directly attached, custom gold-plated RJ45 plug on the other. You plug your existing network cable into the socket and push the CAD Ethernet Control straight into the Ethernet port of your server, computer, streamer or DAC. CAD deliberately chose a direct plug instead of a short cable, to keep impedance as low as possible.
CAD recommends placing it at the point where the network cable enters your audio system. You can also try it at the switch or router, and several units can be used at different points in the network. It is compatible with any device that has an RJ45 connection, including routers, switches, streamers, DACs and amplifiers. If you are optimising your network chain further, read our news on the Silent Angel N8S network switch.
Hand-made in the UK
Each CAD Ethernet Control is hand-assembled and individually tested in the UK. The compact case is made of non-conductive acrylic, which also dampens vibrations. Reviewers have been positive: Roy Gregory of GY8 called it “a bargain of monumental proportions”.
Pricing and availability
The CAD Ethernet Control is available now. At its launch in February 2024, it cost £1,250 in the UK. The CAD web shop currently lists it at $1,400. More information is available on the Computer Audio Design website.
Key specifications
- Type: inline Ethernet noise filter
- Technology: CAD noise reduction, proprietary transformers with galvanic isolation
- Filters: differential Ethernet signals, signal ground, device Ethernet interface
- Connections: RJ45 socket, directly attached gold-plated RJ45 plug
- Compatibility: servers, computers, routers, switches, streamers, DACs, amplifiers
- Housing: non-conductive acrylic, vibration damping
- Production: hand-assembled and tested in the UK
- Price: $1,400 (CAD web shop); £1,250 at launch
