Dolby Atmos: Capturing, collaboration, and mix for live performance

Dolby Atmos is a game-changer, quickly becoming the preferred delivery format for many streaming services, studios and film distribution partners. This advancement has yet again positioned post-production teams at the forefront of pre-production planning. Bringing together Post Audio Teams, Post Supervisors with the production and on set technical teams, communication and collaboration at this early stage is absolutely key to unlocking to potential of Dolby Atmos.

This article explores some key considerations for capturing and delivering high-quality Dolby Atmos audio for live events such as stand-up, stage and arena performances.

Understanding Dolby Atmos

Dolby Atmos expands traditional surround sound by adding elements such as height channels, enabling the creation of a 3D audio environment. Atmos allows sound objects to move freely within this space, offering a lifelike experience. For live recordings, this means the focus on capturing sound with the intention of leveraging this spatial freedom in post-production is crucial.

Pre-Production Planning: Laying the Groundwork

Effective Dolby Atmos recordings start with thorough pre-production planning. Collaboration at this stage is crucial, just as in aspects like VFX planning or OCF capture. The post team must understand what is being recorded to plan their work effectively, while recordists need to grasp the delivery requirements and creative intent to help inform the strategic placement and set up of microphones.

Key considerations include:

Venue Assessment:

• Acoustic Environment: Understanding the venue's acoustics is essential for microphone placement and equipment choice. Large theatres or arenas may have long reverberation times, while outdoor stages could introduce unwanted noise. Addressing these factors early helps in capturing clear sound.
• Audience and Ambient Noise: Capturing audience interaction and background noise correctly allows better control during the final mix.

Microphone Placement and Selection:

• Multi-Microphone Array: A comprehensive setup is essential for Atmos recording. This includes mics close to performers, around the stage, and throughout the venue. Ambisonic microphones, which capture 360-degree audio, are particularly useful for creating an immersive experience.
• Spot and Height Microphones: Strategic placement of spot and height microphones is crucial for capturing key sound sources and enabling vertical audio placement, which is central to the Atmos experience.

Signal Flow and Recording Chain:

• High-Resolution Recording: Dolby Atmos demands high-resolution audio capture (at least 24-bit/96kHz) to provide the best options for mixing.
• Redundancy and Backup: A backup system is critical for ensuring no audio is lost during live recording.

On-Site Recording: Capturing the Moment

During on-site recording, focus shifts to monitoring and adjusting the setup to ensure accurate sound capture.

• Live Mixing vs. Multitrack Recording: For Dolby Atmos, multitrack recording is preferred over live mixing, allowing greater control during post-production.
• Monitoring: On-site monitoring with tools that provide a binaural downmix can help approximate the Atmos experience. Discuss monitoring options with the on-set sound team as this area continually evolves.

Post-Production: Crafting the Dolby Atmos Experience

The mixing stage is where Dolby Atmos truly shines, bringing the event to life with a 3D soundscape.

• Mixing for Immersion: Dolby Atmos allows for object-based mixing, enabling dynamic movement of sounds within the 3D space. Layering direct sound, ambient noise, and environmental sounds creates a rich, immersive experience.
• Utilizing Height Channels: Height channels offer opportunities to elevate certain sounds, enhancing the sense of space and immersion.
• Audience and Ambient Sound: Capturing and integrating ambient sounds and audience reactions is crucial for creating an authentic live experience. Spatial accuracy in these elements helps maintain the realism of the recording.
• Final Mastering and QC: Ensuring the Atmos mix meets platform specifications and includes necessary downmixing options (7.1, 5.1, and stereo) is vital for flexible delivery.

Conclusion: The Art and Science of Dolby Atmos Recording

Achieving the best outcome in Dolby Atmos recording hinges on early and effective communication across teams. Aligning creative intent with technical possibilities during pre-production ensures a deeply immersive audio experience. As Dolby Atmos continues to revolutionize sound, mastering live recording techniques for this format will be increasingly crucial for sound engineers and production teams, ensuring audiences receive the full impact of their work.