Topics covered in this article:
- Different configurations of the Dolby Atmos Renderer
- DAWs and the Dolby Atmos Renderer
- System clocking and synchronization
- Monitoring for Dolby Atmos
- Video monitoring
Different Configurations of the Dolby Atmos Renderer
The Dolby Atmos Renderer software can be run:
- Internally on the same workstation as the DAW
- Externally on a dedicated Rendering and Mastering Workstation
- Natively using a Renderer built into select DAWs
When run externally on a dedicated Rendering and Mastering Workstation (RMW) six platforms and I/O configurations can be used. A Dolby reseller provides these configurations:
- Windows 10 (custom configured Dell 7920) with RME HDSPe MADI and Synchronization I/O
- Windows 10 (custom configured Dell 7920) with RME MADI FX I/O
- Windows 10 (custom configured Dell 7920) with RME MADIfaceXT I/O
- Windows 10 (custom configured Dell 7920) with Focusrite PCIeR Dante I/O
- Mac (minimum Mini or Pro specs) with Focusrite PCIeR Dante I/O
- Mac (minimum Mini or Pro specs) with RME MADIface XT I/O
A more in-depth discussion of these options and their configuration follows in the next Module.
DAWs and the Dolby Atmos Renderer
A DAW is the creative platform for immersive audio and is the source for Bed and Object audio, OAMD, and Longitudinal Time Code (LTC) for the Dolby Atmos Renderer.
A number of DAW platforms work with the Dolby Atmos Renderer.
For the purposes of this training, we will be discussing using the Dolby Atmos Renderer with Avid Pro Tools Ultimate, which was the first DAW to work with the Dolby Atmos Renderer and has a significant market share in both audio post-production and music production environments. Going forward references to Pro Tools refers to the use of Pro Tools Ultimate. Other DAWs and their configurations are discussed in Modules 5 and 11.
It is recommended that the DAW be able to pass 128 tracks of audio to the Dolby Atmos Renderer. While 128 inputs to the Dolby Atmos Renderer are not required to create compelling content, having this capacity does guarantee the flexibility needed and the ability to move projects between DAWs and studios.
Other considerations include the need for high-speed storage. Although this is a general requirement for high track-count projects, storage speed and capacity need extra attention for internal Renderer workflows and if Re-renders are to be recorded to the same workstation.
Dedicated control surfaces are another option that should be considered. While some mixers work well with a mouse, a dedicated control surface can provide even greater efficiency when working with immersive audio. A wide variety of solutions exist at various price points, especially for use with Pro Tools.
System Clocking and Synchronization
For studios with the Dolby Atmos Renderer running on a dedicated RMW, a master system clock (MC) is required and likely already in place. This should be a Word Clock (WC) generator with distributed outputs to the DAW interfaces and Renderer hardware. For Dante systems, a single device locked to WC should be used if the network is not clocked to a PTP clock using the same source. Daisy-chaining, meaning connecting WC through multiple devices rather than distribution directly from the source, should be avoided.
A stable system clock is essential to prevent the Dolby Atmos Renderer from dropping out of record due to discrepancies between LTC and sample position.
For studios using the Dolby Atmos Renderer running on the same workstation as the DAW, a dedicated master system clock may not be necessary, depending on the interfaces and configuration being used.
The Dolby Atmos Renderer chases LTC from the DAW. The LTC source can be a synchronization interface with an LTC generator, such as the Avid Sync HD, or the supplied Dolby LTC Generator plug-in.
The latency value between audio and LTC varies depending on the Renderer and hardware configuration. Preset values are populated in the Renderer for each use case, and the latency value can be adjusted in the Dolby Atmos Renderer software.
Monitoring for Dolby Atmos and Monitor Controllers
A 7.1.4 reference speaker layout is recommended for mixing in Dolby Atmos for post production. For Dolby Atmos Music, an extended layout of 9.1.6 can also be utilized. However, it is understood that this is not practical for many facilities. While it is better to mix with more speakers, it is acceptable to mix Atmos content on 5.1.4 systems. The four height speakers should be actual overhead speakers, as upward-firing consumer speakers are not suitable in acoustically treated studios environments.
Note: Speaker placement, calibration, and tuning are covered in separate documentation.
Monitoring via headphones using the Binaural renderer built into the Dolby Atmos Renderer is useful for checking mixes and working on the go. Mixes should always be checked on loudspeakers prior to delivery.
Attenuation and speaker mute and solo functions can be achieved in the Dolby Atmos Renderer. However, dedicated 7.1.4 capable monitor control systems provide greater control and will add full B-Chain functionality and source switching if needed.
Video playback from the DAW via a dedicated interface is required for post-production work. Many PCIe or Thunderbolt options are available.
Previous: Module 1.2 – Beyond Multichannel Audio