AES/EBU cable, or AES3 is a digital audio cable used for professional audio applications. The term "AES/EBU" stands for Audio Engineering Society / European Broadcasting Union, the organization that developed the standard. According to this protocol, the two channels of audio are run on a single cable.

It is a shielded twisted pair cable designed to carry high-quality, balanced digital audio signals between professional audio equipment, such as digital mixing consoles, audio interfaces, or recording systems.

AES/EBU (AES3 standard) is primarily designed to handle two channels of digital audio (stereo) per connection. This is the most common implementation, supporting two channels of PCM audio at up to 24-bit depth and 192 kHz sample rate. For more channels, you have to use multiple AES/EBU cables or MADI standards.

There are two subtypes of AES/EBU cable: one is AES3 using 110 ohm shielded twisted pair (STP) cable with XLR connectors up to a distance of 100 meters. The other is an AES3id 75-ohm coaxial cable with BNC connectors for up to 1,000 meters.

AES/EBU cables are renowned for noise-free, high-quality sound carried over long distances. It is the best cable for professional 2-channel setups, but an overkill for most consumer setups.

Key characteristics of AES/EBU cables:

1. Balanced connection: It uses a 3-pin XLR connector with balanced audio signals or BNC connectors for a longer distance installation, which helps reduce noise and interference over long cable runs.
2. Impedance: The cable typically has an impedance of 110 ohms, which is essential for maintaining the integrity of the digital signal. The coaxial cable for longer distances has an impedance of 75 Ohm.
3. Data format: AES/EBU cables can carry stereo audio data or multi-channel audio in a digital format. The signal type is digital audio (AES3 standard).
4. Applications: Commonly used in broadcasting, studio recording, and live sound environments.
5. Length: The cable can support a length of up to 100 meters without signal degradation.
6. AES/EBU maintains the integrity of the digital audio signal over long distances without degradation, unlike analog signals which can suffer from signal loss. With AES/EBU, the signal from the source (FOH) to the amp on stage is identical. This ensures that the quality of sound remains consistent and there’s no loss of high frequencies or dynamics.

AES/EBU Cable Applications:

• Professional audio recording studios
• Live sound shows and broadcasting
• Digital audio mixing consoles
• Audio interfaces and DACs (digital-to-analog converters)
• High-quality digital audio transmission over long distances
• High-quality multi-room audio systems
• Theatrical and stage productions
• Mastering studios

When using digital outboard gear (like digital compressors, reverbs, or EQs) with AES/EBU, you're able to send and receive pure digital audio without converting it to analog. This minimizes potential degradation from Digital-to-Analog (D/A) and Analog-to-Digital (A/D) conversions.

In broadcasting, AES/EBU eliminates confusion with foreign network affiliates and trucks by ensuring consistent, high-quality digital audio transmission without the complications of multiple signal formats or conversions.

AES EBU vs. XLR

AES/EBU and XLR are related but not the same:

• AES/EBU is a digital audio standard used to transmit high-quality digital audio signals.
• XLR refers to the type of connector commonly used with both analog and digital audio cables, including AES/EBU cables.
• AES/EBU typically uses XLR connectors, but it is a digital audio protocol, specifically for carrying digital signals (using a balanced 110-ohm cable).
• XLR connectors are used for both analog and digital audio cables, but when someone refers to XLR cables alone, they are often talking about analog audio cables with 3-pin XLR connectors.

In summary, AES/EBU often uses XLR connectors, but XLR cables can also be analog. It’s the type of signal (digital vs. analog) and the impedance (110 ohms for AES/EBU) that differentiate them.

AES EBU Vs. SPDIF

SPDIF is a consumer-level digital audio standard, while AES/EBU is designed for high-quality, professional-grade audio transmission over longer distances. SPDIF and AES/EBU are not compatible; you have to use a signal converter to convert between the two. SPDIF is sometimes referred to as a consumer version of AES EBU. It has a lower signal voltage.

Connection type: SPDIF uses RCA or optical (unbalanced) connections, while AES/EBU uses XLR (balanced) or BNC for longer-distance setups.

Impedance: SPDIF is 75 ohms; AES/EBU is 110 ohms.

Distance: AES/EBU can transmit signals over 100 meters, whereas SPDIF is limited to 10 meters for coaxial.

Use: SPDIF is common in consumer audio devices, while AES/EBU is used in professional audio environments.

Audio quality: AES/EBU supports higher resolution and better performance for professional applications (up to up to 24-bit / 192 kHz audio compared to SPDIF 24-bit / 96 kHz audio). SPDIF supports uncompressed PCM stereo audio, while SPDIF is for compressed formats (e.g., Dolby Digital, DTS).