Welcome to AUX I/O in Pro Tools 2022.9

Routing audio between applications and tools, such as with external renderers and workstations, can be challenging to users depending on their configuration. Thanks to Pro Tools 2022.9, new I/O routing options are possible with the AUX I/O feature. 

New Aux I/O feature in Pro Tools I/O Setup

macOS users have come to rely on Core Audio aggregate devices to solve this challenge. The audio device creation allows them to aggregate multiple audio interfaces (physical or virtual) and use them as a single entity. That said, what about the scenario of HDX based playback hardware that can’t be aggregated and that needs to be used as the Pro Tools playback engine? What about which audio bridge solution to use reliably between applications? What about preventing possible digital audio loops that are prone to happen on patch errors using an audio bridge?

The new proposed feature by Avid Technology addresses those questions. 

New Pro Tools Audio bridge

At the heart of AUX I/O is the Pro Tools Audio bridge. These new virtual core audio devices now get installed with Pro Tools 2022.9. Together with AUX I/O, it offers flexible and simultaneous audio routing in and out of Pro Tools.

Audio bridge configurations in 2, 6, 16, 32 and 64 channel versions are available for flexibility and separation when routing to various applications simultaneously on the same computer.

You can use these new devices in AUX I/O setup, Audio Midi Setup, Sound and Preferences, and input and outputs for other applications such as the SPAT Revolution rendering engine. 

Routing to SPAT Revolution with AUX IO

The steps to getting this done are pretty simple; access the Aux I/O section of the I/O Setup, select In device, select Out device, and you are set. These new inputs will become apparent to the Input section, the same goes for the output. You can take the time to give them a unique name, such as “Bridge to/from SPAT Revolution” as an example.

Creating a bridge for inputs and outputs to SPAT Revolution

You simply need to choose these virtual audio interfaces in the SPAT Revolution Hardware I/O set up to complete this configuration.

Pro Tools Audio Bridge 64 as input, and 32 as the output of SPAT Revolution Hardware IO

Pro Tools versions and AUX I/O capabilities.

Pro Tools Ultimate has unlimited I/O capabilities, where Pro Tools Studio gets unlimited inputs and only 32 outputs (which would be the maximum object you can send to SPAT Revolution to render). Be reminded that Pro Tools installed virtual audio bridge device receives a maximum of 64 channels. Other solutions need to be used for a higher channel count.

Structure for your Pro Tools session and your audio objects.

Last but not least is your Pro Tools session and how you are taking advantage of the newly created audio routes in Pro Tools. Thanks to routing folders introduced in 2020.3, There is a very nice way to keep the object-based workflow organized and routed in Pro Tools. Session templates using this mechanism are available inside the Pro Tools section of the SPAT Revolution User Guide. Furthermore, the following article, Using Pro Tools routing folders with SPAT Revolution dives on this conversation.

Pro Tools Routing folder as your SPAT Objects routed to your Bridge to SPAT