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Pros and Cons of the Integrated Dolby Atmos Renderer in Logic Pro

Edgar Rothermich

In his new book "Mixing in Dolby Atmos - #3 Using Logic Pro", Edgar Rothermich explains the details about both using the Dolby renderer and the built in Logic pro renderer. Should you create your Dolby Atmos mix with the standalone Dolby Atmos Renderer app or the built-in Dolby Atmos Renderer, now fully integrated in Logic Pro v10.7?

In this article, he explains the individual pros and cons. Here is a screenshot from the book showing a feature comparison for both workflows.

Dolby Atmos Support

Before I get into the details of the comparison, I want to clarify something that often causes confusion when checking a DAW to find out whether it "supports" Dolby Atmos or not. I like to group DAWs into four main categories that determine if you can use them to mix in Dolby Atmos.

• Integrated Dolby Atmos Renderer: Logic Pro, Nuendo, and DaVinci Resolve fall into this category because they have the Dolby Atmos Renderer integrated as part of the DAW. That means you don't need the standalone Dolby Atmos Renderer app to create your Dolby Atmos mix. However, you have to read the fine print because a DAW might not provide the full feature set of the Dolby Atmos Renderer app, as we will see in this article when we look at Logic Pro.

• Integrated Dolby Atmos Tools: Pro Tools is the best example for this category because it doesn't have the integrated Dolby Atmos Renderer. However, it has many integrated tools and functionality that enhance the workflow to operate with the standalone Dolby Atmos Renderer app.

• No Support for Dolby Atmos ... But: Ableton Live and even Logic Pro prior to v10.7 are DAWs that don't "know" anything about Dolby Atmos. However, you can still use those types of DAWs to create a Dolby Atmos mix when you use them together with the standalone Dolby Atmos Renderer app because Dolby has several Plugins that enable the DAW to "talk" to the Dolby Atmos Renderer app.

• No Support for Dolby Atmos - Period: GarageBand is an example of a DAW that you definitely can't use to create an Atmos mix because it doesn't have the basic multichannel routing architecture required to handshake with the Dolby Atmos Renderer app.

Logic Pro - Advantages

Now let's look at the advantages when using the integrated Dolby Atmos Renderer in Logic Pro.

  • No additional software or hardware is required: This might the biggest advantage for some users, cost. You don't need to spend the $299 for the Dolby Atmos Renderer app. This is great if you want to just play around with this format, but keep in mind that Dolby also offers a 3-month free trial for the Renderer app.

  • Less of a learning curve: Because the integrated solution in Logic has a limited feature set, it also has the advantage that you have less stuff to learn. You can concentrate on the basics without being overwhelmed with too many options.

  • Sample Rate independent: The required sample rate for the ADM BWF master file of a Dolby Atmos mix at 48kHz. That means the project in your DAW has to be recorded in 48kHz. This could be an issue with existing projects recorded in a different sample rate, but you want to mix them in Dolby Atmos. Logic Pro has a great feature that automatically sample rate converts a project in the background if the current audio interface is not able to playback the project's sample rate. This capability is also applied to a Dolby Atmos. Your Logic project can be at any sample rate and Logic converts the audio signal (in real-time) going into the Renderer and coming out of the Renderer to 48kHz. Even the ADM BWF file export is converted if necessary, so it will be 48kHz.

  • Built-in routing, almost transparent: This is another big advantage, especially for musicians who don't want to get too technical when mixing their content. Using the standalone Dolby Atmos Renderer app requires some routing configuration between the DAW and the Renderer app, plus the proper understanding regardless of whether you run the Renderer app on the same computer or a separate computer. With the integrated solution in Logic, all that is reduced to just basic routing tasks inside Logic. Although, there are some routing specialties you have to learn.

  • Built-in 3D Object Panner: Bed Tracks are routed using the conventional Surround Panner, and Object Tracks are routed using the new 3D Object Panner, part of the new tools in Logic Pro. There is no need to install the separate Dolby Atmos Music Panner plugin. Using Logic's powerful Step Sequencer lets you create tempo-based pan automation, a procedure that I describe in my book.

  • No additional LTC sync required: Using the standalone Dolby Atmos Renderer app requires to sync it with the DAW via a timecode signal. Of course, with the built-in Renderer, this is just one more configuration procedure you don't have to worry about.

  • Automatic Stereo Object assignment: Objects are always mono, and when using a Stereo Object Track, the stereo signal has to be routed/assigned to two individual Objects. This requires some attention regarding the proper configuration on both sides when using the standalone Renderer. In Logic, all that is not necessary. When you change a Track to an Object Track, the corresponding audio and pan metadata assignment (to one or two Objects) is done automatically. You just see a list of the mono and stereo Objects named after the Tracks listed in the same order as your mixer.

Logic Pro - Limitations

Here is the list of limitations of the integrated Dolby Atmos Renderer in Logic Pro. However, it depends on your projects and your personal needs whether this imposes limitations in your creativity or technical workflows. Keep in mind that the Dolby Atmos integration in Logic is fully functional and can create the final Dolby Atmos Master File (ADM BWF) to deliver to your record company or aggregator for upload to the streaming music services. You can decide if a specific feature omission is a dealbreaker and requires to use of the standalone Renderer workflow. Apple could have decided to keep the implementation and usability simple, or might add some currently missing features in future updates as usual with software applications.

  • Only one Bed: One significant limitation in Logic is that it only has a single Bed, the default bed of channels 1-10. However, it depends on your personal workflow if this is an issue. With standard workflows for film mixes, this might be a bigger problem than for music productions, where engineers are still developing workflows and best practices. You can even configure a Dolby Atmos mix with Objects only, so it is up to you. Keep in mind that using the standalone Renderer app with Logic, you are still limited to a single Bed due to Logic's surround bus architecture.

  • Objects are automatically assigned to Input Channels: Although I listed this one as an advantage, it might also be considered a problem for more advanced mixing workflows. There are some workflow solutions where you assign specific ranges of Object inputs to specific Binaural Render Modes and use that as a mixing template. This has advantages later on when compiling multiple ADM BWF files for album creations.

  • No MP4 export option to check for Apple's Spatial Audio compatibility: The "predictability" about how your Atmos mix sounds when played back on Apple Music through their Spatial Audio engine is a hot topic in the audio production community. At least the Dolby Atmos Renderer app provides an MP4 export feature that lets you monitor your mix offline on your Apple devices (see this Production Expert article for details about that). Logic doesn't have that MP4 export feature which is one of the big omissions.

  • Speaker Layouts up to 7.1.4 only: While the standalone Renderer app provides a dedicated speaker setup of up to 11.1.10, Logic can only render up to a 7.1.4 speaker configuration. In addition, you cannot configure any speaker combination, and instead, you are restricted to a selection of six renderer options (Binaural, 2.0, 5.1, 7.1, 5.1.4, 7.1.4).

  • Only six speaker formats available for channel-based outputs up to 7.1.4: The same limitation of six options with a maximum of 7.1.4 applies to the bounce feature to render the mix to a channel-based audio file.

  • No adjustable Trim and Downmix Controls: Logic doesn't provide any options to configure the Trim and Downmix Controls that determine how your Dolby Atmos is rendered to 7.1, 5.1, and stereo. This is the important metadata that is included at the end in the ADM BWF file and used to create the final distribution file, the DD+JOC codec.

  • Import/Export ADM BWF only: Logic only allows to import/export the ADM BWF but not the Dolby Atmos Master File set (DAMF). For that, you have to use the Dolby Atmos Renderer app.

  • Loudness measurement relies on Loudness plugins: Only the standalone Renderer app provides an elaborate real-time Loudness Measurement and offline Loudness Measurement files that are automatically applied to the 5.1 downmix (Dolby specs). However, you can use Logic's built-in Loudness and Level Meters or third-party plugins for that task. Just make sure to set the Monitoring Format in Logic's Dolby Atmos plugin to 5.1 before measuring the Integrated Loudness.

  • No Spatial Coding Emulator option: The DD+JOC encoder applies a "Spatial Coding" algorithm that limits the spatial resolution to reduce the file size. The standalone Renderer app has an option to apply a real-time emulation of that effect when monitoring your mix and. Logic doesn't have that.

  • No Soft-Clip Limiters: The Dolby Atmos playback system has various soft-clip limiters in place to avoid clipping at various stages when levels increase due to level build-up caused by the renderer. The standalone Renderer app has up to three gain-reduction meters that indicate when your mix hits those limiters. Logic doesn't have that.

  • No Bass Management option: The standalone Renderer app also has a simple bass management feature that is not available in Logic.

  • No Speaker Calibration options: Another feature that is not available in Logic is the Speaker Calibration. The Dolby Atmos Production Suite lets you adjust Levels and Delays for each speaker channel, and the more expensive Dolby Atmos Mastering Suite provides the additional EQ settings. Although that configuration is not available in Logic, you can do a similar configuration using the existing Plugins as I describe in the next section.

Speaker Calibration - Logic Style

Here is a setup on how to accomplish speaker calibration in a Logic Pro Atmos Project using the built-in plugins:

  • On the Master Channel Strip ➊ place the following three Logic Plugins on the Audio FX Slot after the Dolby Atmos plugin and after any Meter plugins. The Channel Mode at this point is 7.1.4.

  • The Multichannel Gain plugin ➋ works natively in 7.1.4. It lets you adjust the Gain of each individual channel.

  • Load the Sample Delay plugin ➌ in Multi Mono Mode. Click the Action Button (ellipsis) on the Plugin Window to switch to the Configuration View and set all speaker channels to the "hyphen" ➍. That means none of the channels belongs to a group. Each channel will now be displayed as an individual button ➎ on the Plugin Window, representing an individual instance of the plugin. Select a channel button and adjust the delay individually for that corresponding channel.

  • Load the Channel EQ Plugin ➏ in Multi Mono Mode and do the same ungrouping in the Configurations View to have access to each individual channel ➐ and set their EQ accordingly.

  • Make sure to save each plugin as a Plugin Preset so you can quickly load them in the next Dolby Atmos Project. Even better, save the Master Channel Strip as a Patch to load it later with all the Plugins preconfigured.

Further Reading

I hope you find the information in this article useful. If you want to learn more about Dolby Atmos, please check out my three-part book series "Mixing in Dolby Atmos", part of my Graphically Enhanced Manuals (GEM).
The books are available as pdf, iBook, Kindle, and printed book with all the links on my website.

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