Digital Audio Interfaces and Formats – What gives?
In the 1980’s, as digital audio was in its infancy, manufacturers developing hardware had no choice but to create their own digital formats. Unfortunately, this meant the devices were incompatible, so none could be connected to each other. This is why there were so many formats such as AES/EBU, S/PDIF, ADAT, TDIF, MADI, AES3-id, and several others.
What is a Digital Interface?
Since different digital formats were incompatible when directly plugged into each other, the market was soon demanding a way to help these devices communicate. Digital interfaces provided a solution that could be connected between the devices and internally convert, or translate them into the same format. Now you could utilize devices from different manufacturers together without being plagued by previous incongruencies.
What is AES/EBU?
In 1985, to try and solve the issue of digital formats, the Audio Engineering Society (AES) and European Broadcast Union (EBU) created 2 open-source digital interfaces for stereo and multi-channel audio. These are commonly referred to as simply “AES” or “AES3” and “MADI” (Multi-channel Audio Digital Interface). The AES/EBU format made the transition to digital audio feel less foreign to users since it utilized a standard and familiar XLR connection, which was also cost-effective since no proprietary connector was needed.
What is S/PDIF?
Sony and Phillips entered the digital audio realm with a domestic format of their own, S/PDIF, which utilized both coaxial (phono) and Toslink (optical) connections. The auxiliary information and metadata for AES/EBU and S/PDIF differ slightly, but the audio formatting is the same, meaning both can be interconnected without much trouble.
What are “bits” and “kHz”?
Bits are the basic unit of data when transferring digital audio. Bit depth refers to the dynamic range while bit rate refers to the speed and playback quality. Kilohertz, or kHz, refers to bandwidth and is related to the speeds of bits per second. Greater bandwidth means faster data speed overall.
So let’s say you’re trying to connect a pair of Edifier R1280DB speakers, which use S/PDIF, into an Allen & Heath Qu-24 Digital Mixer, which uses AES/EBU. What would you need between them in order to make that connection work?
Compatible Audio Interface Products
S/PDIF Optical (Toslink) to AES/EBU
The Hosa ODL-312 is designed to take S/PDIF Optical to AES/EBU. This is a 2-channel interface that can do simultaneous conversion in both directions if required, and supports up to 24-bit/96 kHz S/PDIF audio.
S/PDIF Coax (RCA) to AES/EBU
The Hosa CDL-313 is designed to take S/PDIF Coax to AES/EBU. This is also a 2-channel interface that can do simultaneous conversion in both directions if required, and supports up to 24-bit/96 kHz S/PDIF audio.
*Be aware that these are digital format converters, not to be confused with analog-to-digital converters, which function very differently.
To learn more about the Hosa digital interfaces and where to purchase, follow the link here.
Hosa