8c AES Input

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Introduction

AES3 is a standard protocol for the exchange of digital audio signals between professional audio devices, also known as AES/EBU. AES3 was jointly developed by the Audio Engineering Society (AES) and the European Broadcasting Union (EBU). The standard was first published in 1985 and was revised in 1992 and 2003. AES3 has been incorporated into the International Electrotechnical Commission's standard IEC 60958, and is available in a consumer-grade variant known as S/PDIF.

Background

One aim developing the AES3 standard was to allow for the reuse of cable networks established for analog audio signal transmission for digital data transmission. These networks are often hunderds of kilometres long in facilities as broadcast studios. To transmit digital signals over these balanced, analog audio cables some conditions had to be met, which 'shaped' the AES3 standard. More information.

Specifications

An AES3 signal can carry 2 channels of PCM audio over several transmission media including balanced lines, unbalanced lines, and optical fiber. In total, four different kinds of physical interconnection types are defined by the IEC 60958 standard, three of which are in common use. Only type 1 is defined as a professional audio protocol, all other types often used in consumer audio installations. Types 2 till 4 are often called S/PDIF connections.

IEC 60958 Type 1 - Balanced XLR

This type is often used in professional installations and are considered the standard connector for AES3 protocol. The XLR cable should be a 3 conductor with a 110-ohm twisted pair cabling with XLR connectors. Note that the 110-ohm impedance of the cable is very important for maintaining signal integrity. Connector should be from end to end, male-to-female XLR.

IEC 60958 Type 2 - Unbalanced RCA

Type 2 uses an unbalanced, 75-ohm, 2-wired coaxial cable with RCA connector. Note that the cable should be coaxial, not a standard unshielded 2-wired cable, otherwise you would not maintain the required 75-ohm cable impedance. Again, if the 75-ohm impedance is not maintained, signal loss will occur. Connector should be from end to end, male-to-male RCA.

IEC 60958 Type 3 - Optical fiber F05/TOSLINK

Type 3 uses an optical fiber with F05 connector. The cable is usually plastic, but can also be made of glass. Other commonly name for this cable is TOSLINK. TOSLINK is usually found in television as a digital output. Connector should be from end to end, male-to-male F05/TOSLINK plug.

IEC 60958 Type 4 - Coax BNC

The last type of commonly used connector is the coaxial BNC cable. This type uses a 75-ohm coax cable with at the end a BNC connector. This type is commonly used in the broadcast industry, and not in the consumer or professional audio. It specially created for long distance runs.


Using AES3 with your 8c's

There are multiple ways to connect AES3 or S/PDIF sources to your 8c's. Below are supported setups.

Single 8c

Use a balanced 3-conductor cable of 110-ohm twisted pairs cabling with XLR connectors.

8c aes3 simple connection.PNG


Stereo 8c setup

Use a balanced 3-conductor cable of 110-ohm twisted pairs cabling with XLR connectors. There should be one cable between the source and the shared analog and digital input of the first 8c. There should be a second cable between the first 8c’s THRU output and the second 8c’s shared input. Use an AES3-terminator (supplied with every pair of 8c’s) on the THRU output of the last 8c in the chain.

In the Dutch & Dutch app, go to settings for each individual 8c in the system. Set the placement of each 8c correctly, i.e. left for left and right for the 8c on the right.

Set the 8c’s input to AES using the button on the back of the 8c.

8c aes3 thru connection.PNG


Stereo Y-connected pair of 8c's

Use a balanced 3-conductor cable of 110-ohm twisted pairs cabling with XLR connectors.

8c aes3 y connection.PNG


Using S/PDIF with your 8c's

Direct connection

8c spdif direct connection.PNG

Using a transformer

8c spdif transform connection.PNG

Troubleshooting

Only the first 8c in the chain is playing

Only the last 8c in the chain is playing

There is no sound at all

The sound is intermittent or crackling