Ethernet, BNC and AES Cables

Separate networking, digital audio and clock connections

Start with an equipment diagram and label every connection by function. One cable might link network ports, another carry a digital audio stream and a third provide a separate synchronisation path. Grouping these products in a catalogue makes them easier to find without making them interchangeable. For each link, record exact device models, port labels, format and route length. This makes comparisons meaningful and avoids buying the right looking connector for the wrong purpose.

Read the labels beside the sockets carefully, particularly when several similar connectors share a rear panel. A photograph helps capture those labels, but the manual supplies the actual requirements. An arbitrary adapter is not evidence that two interfaces are compatible. Give audio data, control and synchronisation their own lines in the purchasing specification, with the required number of finished cables for each task. This makes the intended system easier to agree on before equipment arrives at the venue.

Ethernet for networked audio

Choose network cable according to device requirements and the complete route. Dante recommends CAT5e or CAT6 for most of its networks. That recommendation does not establish compatibility between every device with a similar looking socket. Identify the equipment's protocol first, then check its documented cable requirements. Compare jacket markings with the specification of the finished assembly, including its connectors.

A permanent studio and a touring package have different practical priorities. The studio benefits from tidy installation, accessible panels and clear labelling. Stage use adds repeated coiling, mechanical handling and protection around connection points. Include any intermediate panel in the connection diagram. Before ordering a long finished cable, confirm that its length and construction suit the actual network equipment. Also consider access to the connectors once every device has been installed in the rack.

BNC describes a connector, not the complete signal

Select a BNC cable using the port's function and line requirements. For example, the RME AVB Tool manual specifies 75 ohm coaxial cabling for Word Clock. That is a requirement for a particular interface, not a reason to connect arbitrary BNC sockets together. Determine whether the link carries audio data, a clock signal or another type of information, and follow the manufacturer's connection scheme.

Give a synchronisation system its own plan: identify the clock source, the receiving devices and their input settings. Check termination requirements in the equipment manuals rather than adding T pieces or terminators by guesswork. Specify the required cable type as well as BNC connectors at both ends. If several coaxial links serve different functions, label both ends of each by purpose. This is particularly useful when equipment is rearranged or several technicians work on the same installation.

AES over XLR and coaxial AES

RME explains the distinction between AES/EBU and AES3id: the balanced implementation uses 110 ohms and the coaxial implementation uses 75 ohms, with different connectors and electrical characteristics. Choose a digital cable from the port specification. Resemblance to a microphone XLR connection or another coaxial lead does not replace this check. A purchasing description should name the complete interface rather than simply requesting an audio cable.

When two implementations must be joined, establish the recommended matching method first. A product with the desired plug shapes may provide only a mechanical transition when the system requires an appropriate matching or conversion device. Do not treat a successful short temporary connection as validation of a long permanent run. Record the cable part number, length and equipment ports in the studio specification so a repeat order reproduces the tested configuration. Keep information about any interface adapters alongside the main diagram.

Installation checks and functional testing

After routing, check plug seating, strain relief and access for maintenance. A long suspended cable section should not hang entirely from the connector. Label the ends by purpose and compare them with the diagram. In a portable system, pack cables so their connectors cannot strike heavy equipment during transport. Keep damaged items apart from the working stock to prevent accidental reuse. Repeat the functional check after a repair or replacement before returning a cable to regular service.

The test follows the function. For a network, confirm access to the intended devices and the audio route. For a digital audio link, check channel transmission. For a clock connection, inspect the equipment's relevant status. Then listen to or record test material in the actual operating configuration. If interruptions appear, document the symptom and change one component at a time. A connection indicator alone does not prove that every channel is routed correctly or replace an end to end audio test. Complete these checks before rehearsal or recording, while there is time to resolve a problem.

Questions for a useful purchasing specification

Is the most expensive cable necessary? The first requirement is suitability for the interface, distance and working conditions. Compare documented specifications, connector construction and service access. Price and apparent thickness do not establish whether a product matches your port. For an important event, include a tested spare of the required type and make it easy to identify among the other accessories.

How can unnecessary adapters be avoided? Provide a diagram, photographs of labelled ports, exact equipment models and measured routes. State which cables remain installed and which travel regularly. Agree on every link separately, including intermediate panels. After testing, keep the final list of part numbers and lengths for maintenance or expansion. Update that list whenever equipment changes so the next order matches the system currently in use rather than an earlier configuration.