Topics covered in this article:
- Software components and configuration when running the Dolby Atmos Renderer on the same workstation as the DAW
- Synchronization options and configuration when running the Dolby Atmos Renderer on the same workstation as DAW
The Dolby Atmos Renderer licensed as the Dolby Atmos Production Suite is designed to be run on the same Mac as the DAW. This configuration is intended for use in offline editorial, sound design/composition, offline Re-renders, and Master File QC situations rather than mixing. However, it is capable of mastering content that is not highly complex if installed on a Mac with a powerful CPU and appropriately configured storage. There are benefits and tradeoffs of running the Dolby Atmos Renderer internally compared to externally on a dedicated RMW.
Using the Dolby Atmos Renderer internally on the same workstation as the DAW is a less expensive option as a complete Dolby Atmos workstation is contained in one computer instead of two. However, there are limitations:
- General System Overhead. Running the DAW and Dolby Atmos Renderer concurrently can tax the CPU. This is especially true with complex content (i.e., high-track counts, very active panning automation, and a lot of plug-ins running natively). Storage configuration is also a factor as disc read/write speeds can be an issue.
- There is no external clock to WC or Video Reference for the Renderer.
- There is no speaker EQ functionality within the Renderer. This means that external hardware/software may be required for room tuning.
- Support for Speaker array mode is not available which can be a limiting factor in larger mix rooms. (This topic is discussed in more detail in a later article.)
- Only a single DAW can be used. This means that multiple premix workstations cannot be used in a stem-based multiple bed workflow.
- The Renderer Remote application cannot be used. This means the Renderer display and control cannot be run from a separate PC or Mac.
Dolby Atmos Production Suite licenses can be purchased directly from Avid. Three seats are also included with the Dolby Atmos Mastering Suite.
Mac-based digital audio workstation with the following components:
- Dolby Atmos Renderer software installed and authorized with a Dolby Atmos Production Suite license
- Supported DAW software using one of the following:
- Dolby Renderer Send and Return plug-ins
- Dolby Audio Bridge (Core Audio Emulation)
- Templates for Avid Pro Tools Ultimate and Steinberg Nuendo as applicable
Object panning and size metadata is transmitted internally to the Renderer. The DAW establishes communication with the Renderer using localhost as the Renderer address.
With Pro Tools, two methods are available for audio I/O to the Dolby Atmos Renderer:
- Renderer Send/Return plug-ins – The use of Send and Return plug-ins on aux tracks was the initial way the Dolby Atmos Renderer was used on the same Mac as the Pro Tools and is only available using Pro Tools. The Renderer Send/Return plug-ins are utilized via inserts on aux tracks to route audio and metadata to the Renderer. Send/Return plug-ins is selected as the driver in the Renderer UI which also sets the Send/Return plug-ins as the synchronization source. This method has pros and cons:
- Allows Live (real-time) Re-renders
- Allows HDX DSP processing, where applicable
- Does not support automatic delay compensation in Pro Tools
- Requires complicated bussing
- Converting sessions from using the Production Suite to using the Renderer running externally as the Mastering Suite is cumbersome
- Dolby Audio Bridge – Is a core audio emulation that provides 130 channels of DAW output to the Renderer inputs. This method also has pros and cons, but it is far easier to work with. It is also the only method available using DAWs other than Pro Tools:
- Allows for 130 Channels of output from Pro Tools Ultimate 2019.10 or later, Nuendo v8 or later, Black Magic Resolve v16 or later, Merging Pyramix, Logic Pro, Ableton Live, and other DAWs
- Supports automatic delay compensation for plug-Ins in Pro Tools
- Allows synchronization via LTC or MIDI Time Code (MTC)
- Facilitates easier session and project compatibility with the Dolby Atmos Renderer running externally as only the playback engine/audio system needs to be changed
- Allows any core audio hardware with outputs for 7.1.4 monitoring to be used
- Has a one-way path to Renderer; Re-renders must be exported and imported into the DAW
- Does not allow HDX DSP processing for plug-ins on a Pro Tools HDX system, since the Dolby Audio Bridge must be set as the Playback Engine
- Does not allow the use of an Avid SYNC HD peripheral, as this device interfaces via a serial connection to either HDX or HD Native cards which will be inactive due to Dolby Audio Bridge being selected as the Playback Engine
- Has the potential for clocking issues with external hardware which may require the use of aggregate devices as a workaround
The Dolby Audio Bridge is utilized by selecting it as the Playback Engine in Pro Tools 2019.10 and later (or equivalent in other DAWs) and as the core audio input device in the Renderer preferences.
Note that the audio buffer size must be set to 1024 samples in the DAW when using the Dolby Audio Bridge.
If using the Dolby Audio Bridge with playback hardware that is externally clocked, you may need to use the Dolby Audio Bridge configured as an Aggregate Device in Audio MIDI Setup.
More information is available here: Dolby Audio Bridge Aggregate Device Setup.
Synchronization Options and Configuration
When using the Dolby Audio Bridge, synchronization is via MTC or LTC over audio. LTC over audio is recommended. The LTC source can be from the supplied Dolby LTC Generator AAX plug-in for Pro Tools or another type of LTC Generator plug-in inserted on a mono audio track. Alternatively, a LTC audio file (.wav) can be placed on a mono audio track and spotted to the start time that matches the file. Typically, the track with either a LTC Generator plug-in or LTC audio file is bussed to output 129. In the Dolby Atmos Renderer, the External Sync Source set is to LTC over audio, and the input channel is specified accordingly.
By contrast, the Send/Return plug-ins use an internal synchronization mechanism.