AES67 on Mac: Network Audio Made Simple
AES67 is the open standard that lets networked audio gear from different manufacturers talk to each other. With it, your Mac can send and receive dozens of channels over a standard network cable.
Consoles, stage boxes, interfaces and amplifiers are moving audio over the network instead of multicore snakes. The catch is that each manufacturer built its own protocol. AES67 is the common language: an open standard published by the Audio Engineering Society that lets gear from different makers exchange audio without converters.
What AES67 defines
- Audio format: 24-bit PCM (L24), usually at 48 kHz.
- Packets: each packet carries 1 ms of audio, sent over RTP on an IP network.
- Clock: every device follows a shared clock via PTP (IEEE 1588), which keeps audio sample-accurate across the network.
- Streams: a stream is a group of channels, usually up to 8, typically sent as multicast so several devices can receive the same stream.
AES67 does not define how devices find each other on the network. Many use SAP, which announces streams with an SDP description. Others ask you to enter the stream details by hand.
What you need
- A wired network. Wi-Fi is not suitable for live network audio.
- A managed gigabit switch with IGMP snooping and an IGMP querier enabled to control multicast, plus QoS to prioritize clock and audio traffic.
- A network port on the Mac dedicated to audio, ideally separate from your internet connection.
- AES67-compatible devices, or devices that offer an AES67 mode.
- Software on the Mac that speaks AES67 and turns network streams into inputs and outputs for your other apps.
Setting up the network
- IGMP snooping and querier: without them, multicast floods every port and can take the network down.
- QoS: AES67 recommends marking PTP clock traffic with the highest priority (DSCP 46, EF) and audio just below it (DSCP 34, AF41).
- Energy saving: turn off Energy-Efficient Ethernet (EEE) on the switch ports, because it interferes with the clock.
- Addressing: keep all audio devices on the same network and the same address range.
The clock: who's in charge
An AES67 network has one device acting as the clock leader. Everything else follows it. In most cases the leader should be the most stable device, such as the console or the stage box. The Mac usually works as a follower, locking its devices to the network clock.
Receiving and sending on the Mac
- Select the audio network port in your software.
- Browse the streams announced on the network and pick the ones you want to receive.
- The received channels become inputs for other apps on the Mac, such as your mixer or DAW.
- To send, create an output stream with the channels you want to publish. Other devices subscribe to that stream.
Common problems
- Clicks and dropouts: almost always the clock. Check which device is the leader and make sure QoS is set on the switch.
- Stream doesn't show up: the device may not announce via SAP, or multicast is being blocked.
- Sample rate mismatch: make sure everything is running at 48 kHz.
- High latency: raise the receive buffer only as much as you need. Every extra millisecond adds to total latency. See the guide to live sound latency.
Where AudiFlux fits in
AudiFlux sends and receives AES67 streams on the Mac (48 kHz, L24, 1 ms packets, up to 8 channels per stream), follows the network's PTP clock and announces its streams via SAP and SDP so other devices can subscribe. You choose an audio network port separate from your internet connection, and network channels show up in the same grid as your virtual audio devices and interfaces. See also how to route audio between apps on Mac.
Frequently asked questions
Does AES67 work with any networked audio device?
It works with devices that follow AES67 or offer an AES67 mode. Proprietary protocols without that mode can't talk to it directly.
Do I need a special network card?
No. A standard gigabit port works. Ideally, use one just for audio.
Can I use the same switch for internet and audio?
It's possible with well-configured VLANs and QoS, but a separate audio network is simpler and safer on stage.