Part 2 of 4 of our Dolby Atmos Mix Series shows an overview on how to Setup a Pro Tools session for Dolby Mixing by utilizing the Built-In Dolby Renderer in Pro Tools. Avid Master Instructor Andy Hagerman guides you through the process of setting up your Stereo Session into one that can utilize the power of Dolby Atmos.
We advise professional audio engineers to attend the 6-day (24 hours), formal Pro Tools | Dolby Atmos Certification to cover advanced mixing applications where you are working real-time with one of the Avid Master Instructors for the fastest way to bypass any trial and error; hundreds of pages of documentation and techniques are covered.
Sample Rates For Dolby Atmos
If you’re going to mix in Dolby Atmos, your session’s sample rate will need to be either 48 kHz or 96 kHz (you can find out what your session’s sample rate is from the Session Setup dialog box, which you can access from the Setup menu). If your session isn’t either of those two sample rates, your first task will be to create a new version of the session. This is easily done by going to the File menu, and choosing Save Session Copy In. You’ll be presented with a dialog box which will enable you to create a new copy of the session at a different sample rate from the original.
Setting Up Pro Tools
In many ways, mixing in Dolby Atmos is simply an extension of traditional mixing. As with any mixing scenario, good session habits will serve you well. In this example, I’ve got a simple stereo session, but even though it’s basic, I’ve taken some time to make sure that tracks are properly named and colored by what kinds of tracks they are.
In the example below, I’ve got different types of tracks (drums, guitars, and so on) routed to subgroups (in this session, I’m using Routing Folder tracks for that job), and the final output is controlled via a Master Fader. This is typical of basic stereo mixing, and many of these elements we’ll continue to use when we make the jump to Dolby Atmos.
Activate the Pro Tools Dolby Renderer
Before we can do anything else, we’ll need to enable Pro Tools’ internal Dolby Atmos Renderer, so let’s tackle that first:
- From the Setup Menu, choose I/O. The I/O Setup dialog box will appear.
- In the I/O setup dialog box, click the Dolby Atmos tab
- In the upper left-hand section of the dialog box, you’ll see a drop-down menu. From here you can choose whether to use Pro Tools’ built-in renderer or an external renderer. For the purposes of this example, we’ll choose Internal Renderer.
- Click the check box to the left of the drop-down menu to activate the Dolby Atmos renderer.
At this point, your I/O Setup dialog box will look something like this:
Setting Defaults
When you activate the Dolby renderer (by clicking the check box), the main part of the dialog box will often populate with bed and object paths, but not always. If you want to make sure that you’re starting off with a fully-stocked default arrangement, just click the Default button in the lower left-hand section of the dialog box.
When setting your defaults, you have the choice between creating mono objects or stereo objects, which you can set by clicking on the drop-down menu to the right of the button. There is no right or wrong choice here, but my personal preference is to choose Create Stereo Objects, as it will give you access to both stereo objects and mono objects (which will appear as subpaths within each object)
Loudness Re-Renders
In the lower right-hand corner of the I/O Setup dialog box, you can choose the format of your session’s Loudness Re-render. Put simply, this is the format that is used when measuring the loudness of your mix via metering plug-ins. The topic of loudness metering is beyond the scope of this article (but can be learned at Promedia Training) -” for now, stick with the default of 5.1
Headphone Re-Renders
One of the great things about mixing with the Dolby Atmos renderer is the ability to choose a different format for headphone monitoring from the speaker layout in your studio. For example, if you had a 7.1.4 speaker configuration in your control room, you can choose whether to listen to a stereo or binaural mix in your headphones.
Binaural Monitoring and Hardware Buffer Size
Binaural monitoring is only available when using higher hardware buffer size settings (in the Playback Engine dialog box). The specific minimum settings vary based on the session’s ample rate and the kind of system (native vs DSP) that you’re using. If your buffer is too low, a dialog box will appear indicating the minimum buffer setting, as shown here.
Output Setup
Before we leave the I/O setup dialog box, we’ll need to check one last thing in the Output tab: In the lower right-hand corner, you must choose a Monitor Path. It’s important to choose the output path that is connected to your studio monitor speakers (in this case, I’ve named that path "Dolby Speakers"), as this tells the Dolby Renderer which path is connected to your speakers, and how rendering should be processed.
After you’ve made your choice, the monitor path will be indicated with a small speaker icon to the right of the path name.
To save your changes in the I/O dialog box, just click the OK button in the lower left-hand corner.
Setup Tips:
If you want to be able to utilize your headphones as a binaural monitoring option in addition to loudspeaker monitoring, how you set up your output paths matters. You’ll want to set up one path for speaker monitoring and another for headphone (binaural) monitoring. Here are a couple of scenarios:
In this example, we’ve got a 7.1.4 speaker setup, which we’ve assigned to outputs 3-14. We’ve reserved outputs 1-2 for a headphone output for binaural monitoring.
Here’s the other end of that spectrum, in a stereo monitoring environment. Since stereo mixes and binaural mixes are different, we’ll assign separate stereo outputs to speakers and to headphones.
If you don’t have enough output paths for separate headphone and speaker monitoring, don’t worry -” there are ways to work within the renderer window, which we’ll look at next…
Dolby Atmos Renderer Setup
Now that we’ve activated the Dolby Renderer, we can start setting things up in the Dolby Renderer window. When you open the Dolby Atmos Renderer window (from the Window menu, you’ll see your allocation of beds and objects on the left-hand side, your speaker layout and metering on the right-hand side, and a visual representation of the listening space in the center.
Monitoring Setup
The output path that you chose as your Monitoring Path (in the I/O Setup dialog box) will determine the maximum number of speakers that you can utilize in your mixing space. You have some additional control beyond that in the Dolby Atmos Renderer window. Clicking the Monitoring drop down menu (in the upper left-hand section of the window) will give you a list of available formats that you can choose from.
In the example below, we’ve set up a 7.1.4 path as our Monitoring path in the I/O setup, and clicking on the drop-down menu in the Dolby Renderer window will give us a number of options:
You’ll note that when using the Pro Tools internal renderer, not all formats are represented in the monitoring drop-down menu. The internal renderer supports 9.1.6 (Pro Tools Ultimate only), 7.1.4, 5.1.4, 7.1, 5.1, 2.0, and Binaural. Dolby’s stand-alone renderer supports additional formats.
While mixing Dolby Atmos with only two speakers isn’t recommended, it is possible. Here’s what you’ll see if your I/O Setup’s monitoring output path is stereo. You’ll see here that your different options are more limited: stereo or binaural.
Tip: If you have an interface with at least four discreet outputs (as shown in the "Output Tips" sidebar), you have the ability to monitor in stereo through traditional monitoring speakers and binaurally with headphones, without having to switch any settings. If your interface only supports two outputs, you’ll only be able to hear one of those mixes at a time, which you can switch here in the monitoring drop-down menu.
Speaker Layout and Metering
Once you’ve made your choices with regard to your monitoring format, the right-hand side of the Dolby Atmos Renderer window will change accordingly. For example, here’s what you’d expect to see with a 7.1.4 monitoring setup…
Here’s the speaker layout and metering with a stereo monitoring setup. You see why this isn’t a recommended setup -” though within the renderer you’ll see objects moving in a 3-dimensional space, you’ll only hear audio from the two speakers in front of you.
This is also what you’d see if you are monitoring binaurally through headphones (both are two-channel formats). If you’re monitoring binaurally using quality headphones, you’ll hear an emulation of a 3-dimensional space (though many professionals will tell you that it’s no replacement for a traditional loudspeaker monitoring setup). Now that you’ve chosen a monitoring format in the Dolby Atmos Renderer window, you’re ready to close that window and start setting up tracks.
Track Setup In Pro Tools
Once you’ve set up your I/O and Renderer, you’re ready to start working with individual tracks. Now’s the time to start thinking about how to use the beds and objects available to you. As with many conventions in mixing, there’s no single "right answer", and ultimately whatever sounds the best and is the smoothest workflow is the way to go. To start out, though, you might want to consider this commonly-used approach: If a track (or subgroup) doesn’t move around too much, assign them to a bed. For elements that do move within your mix over time, that’s where you employ objects.
Assigning Tracks To Dolby Beds
In the session that I’m using for the images in this article, I’ve got some traditional music subgroups (drums, keys, guitars, and so on), plus one subgroup of effects that support some action that is shown in a video. My general approach will be to assign the subgroups to the bed, each effect track to a separate object, and go from there.
As an example, let’s take a look at my drum subgroup. I’ve traditionally panned the drums and routed them to a stereo Routing Folder track. Let’s keep things simple for now: Clicking the Output selector (in the I/O column) will reveal a new option -“ Bed. Clicking this will allow us to choose any of the beds we’ve created, including any subpaths that have been created within that bed (in the I/O Setup dialog box). We’ll just choose the default bed (named Bed 1-10). When you choose the bed, you’ll see that your stereo panning values turn into a surround display.
Multiple tracks can be assigned to the same bed -” in this regard, it’s similar to traditional mixing. If you’re starting with an existing stereo session and Atmos-izing it, as we are in this example, you might have organized your tracks into stereo subgroups (using an Aux or Routing Folder track as a subgroup master). There are a few different ways that you can approach subgroups, including:
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Assign the stereo stem (drums, guitars, Keys, and so on) to a bed. You’ll be able to position each of the stem’s two channels within Dolby’s 3-dimensional space. This may work for some kinds of stems, but not for others. For example, in the session I’m working with here, I want the drums to be in the front of the soundscape in order to give a sense of solidity to the mix. In this case, a stereo stem going to a bed and panned to the front will do the trick with minimal fuss.
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For some subgroups, you might want to create more of an immersive feel than a stereo subgroup can provide (in my session, my keyboard tracks, though non-moving, should surround the listener on all sides). You can still use beds, but you’ll want to change the stereo submix master (the Aux track or Routing Folder track) to one that can address more channels. Here’s one way to do it.
- Create a new multi-channel Routing Folder or Aux track (if you’re using the standard Dolby bed and want to be able to freely position the members of that group, choose 7.1.4 as a channel width). You’ll use this instead of your previous stereo subgroup master, so if you’ve got plug-ins or sends on the stereo subgroup master, you might want to move them over to the new track.
- Assign the output of the new subgroup master to a bed. (NOTE: If you create a 7.1.4 track and assign it to a 7.1.4 bed, you won’t see any panning control. This is not a bug -” you’ll be doing your panning on the tracks feeding this new subgroup master.)
- Change the output of each member to match the input of the new subgroup master. One easy way to do this is to click the Output selector of each member track, move your cursor to the Track menu item, and choose the new subgroup master track that you created from that list. You’ll see the panning view of the tracks change to show surround panning positions, enabling you to discretely position each member track individually in the bed.
Assign Tracks To Objects
Any tracks that aren’t assigned to a bed (either directly or via a subgroup) will need to be assigned to an object in order to be heard. In my session, I’ve got a number of sound effects that need to move according to some on-screen action, so I’ll use objects for these.
Here’s how to assign a track to an object:
- The first thing to do is to make sure that you’re seeing the Object view (either in the Edit or Mix window -” I’ll show it in the Edit window). Experienced users know that there are a number of ways that you can show or hide views, but if you’re new to Pro Tools, here’s an easy to do it in the Edit window: Move your cursor to the View menu, then to Edit Window Views, and then click Object from the submenu that appears. Shown views are indicated with a check mark.
- Click the object selector on the desired track. If you’ve created default stereo objects, you’ll can easily select stereo objects for stereo tracks, and mono objects for mono tracks. In this example, we’re assigning FX1 (a stereo track) to Object 11-12, and FX 2 (a mono track) to Object 13.
There’s one more step, and here’s where some folks get tripped up. In the image above, you’ll see that after you select an Object for a track, the Object selector is dark blue and the button below it (called the Bus/Object Toggle) reads "Bus". This tells us that even though we’ve chosen an Object, we’re not using it yet. What we are using is the bus that is selected in the Output path selector in the I/O column. This is easily remedied: Just click the Bus/Object Toggle button, and you’ll see that your Object selector will turn into an active color (the previously-used bus will go dark), and the Bus/Object selector will now read "Object".
Tip: If you select a bed as your track’s output, and also select an object for the track, the Bus/Object toggle button will give you the ability to quickly switch between the track’s output from a bed to an object with a click of a button. If you’re unsure as to whether to use beds or objects for a given track, this is a great way of setting things up to give you the ability to switch between beds and objects quickly and easily.
Final Steps
Transforming a stereo session into Dolby Atmos can be tricky, so before we get into the finer points of panning (which we’ll explore in the next article), it’s a good idea to give your session a good once-over, to make sure that all of your tracks are being routed through the Dolby Atmos Renderer, using either beds or objects.
The Dolby Atmos Renderer window gives you a good way to check this: In the upper right-hand section of the window, you’ll see three mute controls:
- Clicking the Mute button will silence the output of the renderer. If you’ve done your work correctly, when you click this button, you should hear nothing as your session plays.
- Clicking the Beds button will mute the output of the renderer’s beds. When you click this, you should only hear the tracks that you’ve assigned to objects.
- Clicking the Objects button will mute the output of the renderer’s objects. When you click this, you should only hear the tracks that you’ve assigned to beds.
Master Fader Control
Once you’ve routed tracks to the Dolby Atmos renderer, what you’ll be hearing will be the renderer, not output paths that we use for traditional mixing. For example, if you had a stereo session with a Master Fader track that was controlling to total output of that session, that Master Fader’s meters would be dark, as you’re not listening through that path any longer.
This too is easily solved: Just create a new Master Fader that matches the format of your monitoring system, and from the Output selector, click on Renderer Out. Now your Master Fader meters will mirror the meters in the Dolby Atmos renderer, and you’ll have overall level control going to your speakers.
Binaural Monitoring (Headphones)
This last bit won’t apply to everyone, but if you’ve set up a dedicated output for headphone monitoring, you’ll have the ability to listen to a binaural mix any time you want.
When you enable the Dolby Atmos Renderer within Pro Tools, you’ll get two new available input choices -” Loudness and Headphones. We’ll explore the Loudness input in a later article, but for now, let’s set up binaural monitoring -” here’s how:
- Create a stereo Auxiliary Input track.
- From the Output Selector, choose the path that is mapped to your headphones.
- From the Input Selector, move your cursor to the re-renders menu item. From the list that appears, choose Headphones.
By choosing the Headphones input, you can hear the format that you chose in the Headphones re-renders setting in the I/O setup dialog box. If you chose binaural in that menu, the you’ll be able to hear a binaural mix just by putting on your headphones.
Of course, if your system only has two outputs (a laptop’s built-in sound, for example), you don’t have the luxury of having simultaneous speaker and binaural headphone mixes, but if you do have the option of setting aside outputs specific for binaural headphone monitoring, this method will set up a track for that purpose, with the volume control of the Aux track enabling you to change the level being sent to your headphones.
That’s it for now, and it’s plenty. In the next article, we’ll explore panning in Dolby Atmos. See you then!
I advise professional audio engineers to attend the 6-day (24 hours), formal Pro Tools | Dolby Atmos Certification to really get into advanced mixing applications where you are working real-time with an Avid Master Instructors both live-online or in-person.
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Author: Andy Hagerman
Avid Master Pro Tools Instructor
Andrew Hagerman has been a professional musician and teacher for the majority of his nearly 60 years. Beginning his musical life at the early age of eight as a tubist and bassist, Andy continued his studies at the prestigious Northwestern University in Chicago, Illinois. During his time there, MIDI and computer music were in their infancy, and Andy recognized the usefulness of these new technologies in aiding the creative process. He had the unique opportunity to learn these tools as they were being created and refined, and his quest for the best in audio and music technology ultimately led him to use and teach Avid’s Pro Tools