Topics covered in this article:
- I/O Setup
- Pro Tools outputs to the Dolby Atmos Renderer
- Bussing/mapping to the Dolby Atmos Renderer
- Pulling the I/O configuration from the Dolby Atmos Renderer
While the Dolby Atmos Renderer installs templates for Pro Tools, it is important to understand how to configure the Pro Tools I/O for use with the Dolby Atmos Renderer. The I/O setups demonstrated in this module are examples of basic configurations. I/O setups for music mixing and stereo workflows are covered in Exercise 1.
The Pro Tools I/O settings must be configured to route signals to the Dolby Atmos Renderer. The exact configuration can vary, depending on the hardware used and the number of Beds and Objects required.
Initially, the Pro Tools I/O should be configured to match the default input configuration of the Renderer – the first 10 inputs for a 7.1.2 bed and the remaining 118 inputs for objects.
To gain a clearer understanding of the routing, it is best to start from a blank slate by deleting existing Output and Bus paths from the I/O Setup.
Click on one output and then press Command+A (Mac) / Ctrl+A (Windows), or hold Shift and click, to select all existing Output paths. Then click Delete Path. Do this on both the Output and Bus tabs.
In the Output tab, click on the Path Order selector at the bottom of the I/O Setup dialog box and set the 7.1.2 channel format to the SMPTE path order.
Note that the Renderer uses SMPTE channel order for 5.1 to 7.1.2 beds. If recording Re-renders back into Pro Tools, SMPTE ordering must be used on both the Output tab and the Input tab. Do not change the channel order on the Bus tab, as this is used for internal routing in Pro Tools.
Outputs can manually be re-ordered in SMPTE order if this step is neglected.
Next, add a 7.1.2 output for the Bed and 118 mono outputs for Objects:
- Click New Path to add the new signal path and assign it to the first ten outputs of the interface. This path will be used to play back Bed audio.
- Click the + icon to add 118 mono Output paths named Object. These paths will be used to play back Object audio.
- Check that these new outputs populate the correct 128 outputs set up for use with the Dolby Atmos Renderer. If you have multiple hardware interfaces connected, these may not necessarily start at Output 1.
Note that in the example above, an output was also added to use the LTC Generator Plug-in. This isn’t necessary if using an AVID Sync HD. This should be allocated to the 129th output.
Additional bed and bus workflows for Dolby Atmos Music production will be explored on the ProTools exercises.
After having created the above outputs, the busses will be created automatically and named for the outputs with Mapping to Output already set in the Bus tab.
The next step is to map the Bed(s) and Objects to the Renderer:
- Highlight the Bed bus. Click on Mapping to Renderer and select the Renderer input 1-10 (7.1.2). In this case only one Bed is being used. If multiple Beds are used, Beds of a common width can be highlighted and assigned sequentially as described in the next step.
- Highlight (Shift-click) Busses Object 1 to Object 118.
- Simultaneously hold Command+Option+Shift, click on Mapping to Renderer for Object 1, and select Input 11. This will sequentially map all Objects to their corresponding Renderer Inputs, beginning at Input 11.
This step ensures that panning and size metadata for each Object is mapped to the corresponding audio input to the Renderer. Additionally, it makes the Beds available in the Edit and Mix windows as a discrete output assignment category separate from Output and Bus. Assigning Beds to the Renderer is not technically required to route Bed audio to the Renderer but failure to do so does bring up a warning dialog when clicking OK to exit the I/O setup as this step is required for bouncing a mix to ADM BWF. This functionality will be discussed in module 8.
Mapping to Renderer (and the ability to map Beds as well as Objects) was introduced in Pro Tools 2020.11 and replaces the Mapping to Object column used from Pro Tools versions 12.8 through 2020.10.
Pulling the I/O configuration from the Renderer
As an alternative to the above steps, the I/O configuration can be pulled from the Renderer. This can be especially useful if a more complex input configuration has been defined in the Renderer.
To begin with this function, first clear the Output and Bus tabs as described above.
From the Bus tab, click on the drop-down menu to the right of the Default button and change from All Busses to Use Atmos Renderer. Click Default and both the Output and Bus tab will automatically populate using the input configuration as currently set in the Renderer. Pro Tools 2021.3 introduced the ability to create stereo or mono busses when pulling the input configuration from the Renderer. While all Objects in the Renderer itself are mono, this feature allows a much more flexible workflow in Pro Tools.
Also introduced in Pro Tools 2020.11, an additional column in the I/O Setup Bus tab. This is the Bed/Object column. When pulling the I/O configuration from the Renderer any existing group names and assignments will also be created. Group naming and assignments can be controlled from the Renderer or independently in Pro Tools as well as from an imported ADM BWF file. This functionality will be discussed later in this module. An example of a multiple Bed I/O configuration with additional input description and group names and assignment populated is shown below.
Note: It is important to realize that the Bed/Object Group column does not “push” any information to the Renderer. It is used exclusively to include Group names and assignments when bouncing a mix to ADM BWF. This will be discussed in module 8.
The image below shows an audio post-production multibed workflow with associated group names. Groups for Dolby Atmos Music workflows will be explored later in Module 7.
It is possible to create stereo outputs with mono subpaths that are mapped to the Renderer. This allows for both stereo and mono tracks to be used as Objects in the session. While this is more cumbersome to set up, it provides for greater flexibility. This subject is covered in a later module.
The Dolby Audio Bridge Stereo template (.ptxt) configures the I/O in this way, with the exception of a track for the LTC Generator plug-in. This can be a useful tool to save time when configuring new sessions.