The World of Sending Audio Over IP
The push towards sending audio over IP has been around as long as road crews and sound engineers have been carrying cables for every single input and output in their rigs. How does this technology help deliver pristine sound and save on chiropractor bills? Continue reading to learn about the many benefits of sending audio over IP.
How Do AoIP Systems Work?
Simply put, Audio over IP (AoIP) systems allow you to transmit multiple uncompressed digital audio signals over ethernet (Cat5/Cat6) cables with minimal latency.
Without getting too deep into the IT world, there are three types of AoIP systems, each of which operates within different layers of a computer network. These layers are used to identify where a signal is within a network and how a device accesses that signal.
- Layer 1 — Physical: Provides point-to-point connections from one device to another using physical cables.
- Layer 2 — Data Link: Provides a link between two devices within a network.
- Layer 3 — Network: Provides a link between two or more devices and allows switching between multiple networks.
It should also be noted that Layer 3 systems can connect directly to existing ethernet ports in your computer, while Layer 2 systems will require an external interface. If that sounds too nerdy for you, don’t worry, most AoIP systems are plug-and-play!
AoIP may seem like a modern development, but it’s actually been around since the 1990s. Today, over a dozen companies have their own protocol for AoIP. Many companies license their tech to hardware companies, while others have created “open” protocols that are available free of charge.
Here’s a quick breakdown of the most popular systems:
- ALC NetworX Ravenna — Layer 3, Open: Used as the basis for developing AES67. Featured in Merging Technologies Horus.
- Audinate Dante — Layer 3, Proprietary: Licensed to over 250 hardware manufacturers. Popular Dante enabled units include Focusrite Rednet, SSL Network I/O and Burl Audio Mothership.
- Axia Audio Livewire — Layer 3, Proprietary: Very popular in the broadcast market.
- AES50 — Layer 1, Proprietary: Used by Behringer on the X32 consoles. Technically a point-to-point system, meaning there are individual inputs and outputs. The ethernet cable carries the signal from the console to the stage box.
- Cirrus Logic CobraNet — Layer 2, Proprietary: Developed in 1996, this was one of the very first AoIP systems.
- Ethersound — Layer 2, Proprietary: Another AoIP innovator, used in the early DigiCo and Yamaha consoles.
- IEEE Audio Video Bridging (AVB) — Layer 2: Interfaces audio and video signals. Popular AVB systems include MOTU, PreSonus, and Avid.
- QSC Q-LAN — Layer 2, Proprietary
- Roland Ethernet Audio Communication (REAC) — Layer 1, Proprietary: Used in V-Mixer system and Cakewalk software.
- Waves SoundGrid — Layer 2, Proprietary: In addition to traditional networking uses for studios, live sound, broadcast, post-production uses, SoundGrid systems are also used to connect DSP servers for additional processing power for using plug-ins in real-time.
AES67: The AoIP Standard
In 2013, the Audio Engineering Society (AES) created an open standard for audio over IP/ethernet interoperability known as AES67. Interoperability is the key word in that sentence. By publishing an open standard, AES hopes to solve the issue that plagues so many other areas of the audio industry — when two pieces of gear won’t “talk to each other.”
AES67 is a set of guidelines for existing and future systems to follow in order to be compatible with one another. It sets a minimum standard for AoIP devices to follow. By following AES standards, your device will be compatible with other AES devices. That’s interoperability — the ability to operate within a computer network.
Which System Is Right for You?
With so many competing systems to choose from, it can be hard to determine which unit is best for you.
First, try to narrow down why you need an AoIP system. If it’s simply to replace long cable runs for standard inputs and output, a Layer 1 system should do the trick. If you need to connect multiple units within a network, browse for a Layer 2 system. And if you need the ability to switch between networks, go with a Layer 3 system.
Leveraging the flexibility of Dante, Focusrite's audio-over-IP devices deliver a modular approach to building up your audio solution, whether for post-production, broadcast, live sound or the recording studio.
Focusrite’s RedNet is the first to offer IP network audio interfaces for the recording studio – or any application that requires moving high-quality audio around with ultra-low latency, and is currently the popular AoIP interface on the market.
The Avid MTRX was introduced in late 2016 and has since become a must-have, as this powerful interface offers flexible routing with Avid control surfaces, Eucon controlled monitor functionality and a massive integrated router. The Dante module for the MTRX gives users 64 channels of digital I/O to use in their post-production facility or recording studio.
MOTU has been utilizing the power of AoIP with their popular AVB systems. Their Ultralite AVB is an 18-input, 18-output audio interface with DSP mixing, wi-fi control, AVB audio networking and best-in-class analog audio quality for on-the-go mobile audio recording. The UltraLite AVB sets a new standard for analog audio performance in a mobile audio interface. The eight balanced analog outputs are capable of 117 dB dynamic range.
Their 112D unit is equipped with a 48-channel digital mixer designed just like a large format mixing console. The 48 inputs can take signal from anywhere including the physical inputs on the interface itself, audio channels from host software on your computer, audio network streams or even mixer outputs.
Apogee Symphony I/O MK II SoundGrid
Apogee is well known for their high-end digital audio interfaces, but their new Symphony I/O MK II Soundgrid unit offers AoIP integration.
The Symphony I/O MKII SoundGrid is a multi-channel audio interface featuring Apogee’s newest flagship AD/DA conversion, modular I/O with up to 32 inputs and outputs, and direct connectivity to the Waves SoundGrid® network.
Choose from four base configurations:
- 8x8 Mk II
- 16x16 Mk II
- 8x8 with 8 mic preamps
You can easily expand as your studio grows, with two module slots and the capacity for up to 32 inputs and outputs of A/D & D/A conversion per unit.
Connect the Symphony I/O Mk II to your computer via Ethernet cable to sync audio between multiple computers, DAWs and rooms. You can also connect to a Waves SoundGrid server for near-zero latency recording with any SoundGrid compatible plugins.
Rupert Neve Designs RMP-D8
Even Rupert Neve, the master of all things analog, has started to bring AoIP technology into his products. The brand new RMP-D8 puts the beautiful punch of Rupert's classic preamps into an interface integrated with Dante that can be used in the live setting, post-production facilities or recording studios.
Burl Audio BMB4
Burl Audio's new BMB4 module extends these connectivity capabilities to the Waves SoundGrid platform for both the B16 Mothership and the B80 Mothership. With 64 I/O channels of Waves SoundGrid connectivity, the BMB4 truly opens up a wide range of options for your workflow, no matter which type of studio or live setting you're working in.
Welcome to the World of Tomorrow
AoIP is becoming popular in audio production facilities all around the world. Studios are using it to seamlessly record from multiple rooms at once. Concert venues and houses of worship are using it to connect their consoles to the stage. Broadcast and post-production facilities are using it to simultaneously send hundreds of high-quality (96kHz, 24 bits) signals to multiple devices.
While AoIP systems are currently more commonly seen in large or high-end facilities, as the technology becomes more accepted, many industry experts expect to see them introduced to small-scale facilities and even home studios in the not-so-distant-future.
This could allow engineers to set up areas to record in various rooms around the house — a walk-in closet for the vocal booth, the bathroom for a reverb chamber, and the hardwood floors in the dining room would be perfect for tracking drums!
Although AoIP has a been around for decades, it’s finally starting to become integrated into the studio world. Systems are becoming more advanced and less expensive every day. When will you make the switch?