Dolby Atmos is a popular immersive audio format that puts the listener in the centre of a 3D sound field experience. It translates across any listening environment from 34 speakers down to binaural audio in headphones.
Now that Dolby Atmos is supported by popular streaming services such as Apple Music, Amazon Music and Tidal, it has become a standard format in addition to stereo for most major label releases. This new immersive format is quite accessible for independent artists and music producers with some additional education and minimal cost.
Because Dolby Atmos encodes down to binaural when experienced in headphones, it is feasible for any music producer to mix in Dolby Atmos without needing an expensive 7.1.4 speaker system, and for consumers to listen with standard headphones.
Although the binaural encoding technology is being continuously improved, it is advisable to get your Atmos mix checked and mastered on a calibrated 7.1.4 speaker system before distribution.
(7.1.4 ~ the 7 means 7 surround speakers - Left, Center, Right Lside, Rside, Lrear, Rrear. The .1 is 1 subwoofer. The .4 are 4 ceiling speakers with 2 in front and 2 in the rear. Refer to the picture at the top of blog to visualize it. The 4 subs in the corner are all on one channel thus remain .1)
Ableton Live sends up to 128 channels of audio to the Dolby Renderer via the Dolby Audio Bridge driver. The Dolby Atmos Music Panning plug-in - loaded on audio tracks in Live - sends 3D panning metadata to the Dolby Render for encoding.
Dolby Atmos uses the terms "beds" and "objects". Audio beds are channels, just like those in 2.0, 5.1, 7.1 configurations which output direct to speakers. Objects are sounds that are placed in a virtual 3D sound field independent from channels. Within Live, the Dolby Atmos Music Panner plug-in sends 3D panning metadata to the Dolby renderer. Dolby Atmos can support up to 118 simultaneous objects. 1-10 are the beds and 11-128 are for Objects. Depending on your preferred workflow, there are different ways to set up Beds and Objects. The process that I have found to be the most effective with Live is using the Beds exclusively for multi-channel audio effects returns and for the LFE (low frequency effects). I use objects for all other sounds.
Tools you will need
Download and install the latest version of:
Be sure to install the Dolby Atmos Renderer, Dolby Atmos Bridge, and Dolby Atmos Binaural Settings Plug-in, Dolby LTC Generator Plug-in
Dolby Atmos Music Panner (VST3)
Configure Ableton Live Preferences
In Live's Preferences Audio Tab set:
Audio Output Device: Dolby Audio Bridge
Sample Rate:48000
Buffer Size: 1024
In the Output Config activate:
Mono Outputs 3,4,129,130 only
Stereo Outputs 1/2,5-128
I suggest labelling the outputs as detailed below.
Sync Ableton Live with the Dolby Renderer
In the Dolby Renderer go to preferences and set the following:
Audio input device: Dolby Audio Bridge
Audio output device: To your audio interface
External sync source: LTC over audio
LTC input channel: 129
Headphone only mode: On (if you don't have a 7.1.4 speaker array)
Routing: 1/2
Frame Rate: 24 fps
Sample Rate: 48khz
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The following steps are a walkthrough of how to create your own Atmos mix template in Live however you can download my Atmos mixing template at the bottom of this article)
Create an audio track in Ableton Live
Assign the Audio Output to 129
Add the Dolby LTC Generator Plug-in to the track
In the Dolby LTC Generator plug-in set the frame rate to 24 FPS
In Live's Options menu set the time ruler format to 24 fps
Turn on Sync in the Dolby Renderer and press play in Live to test the renderer is syncing
Creating Audio Tracks as "Objects" and configuring the Dolby Atmos Music Panner
In this template we are exclusively routing to Objects for any clips that we want to play back.
In Live create an audio track and assign the output to any unused Ext.Outs 11-128. (I reserve 127/128 for my stereo reference track)
Add the Dolby Atmos Music Panner plug-in to the same channel and make sure that it is assigned to localhost and the Object pair is routed to the same as the Ext.Out in Live.
Setting Up the LFE and Multi-channel FX Returns using Beds
Create 6 audio channels in Live for the beds with no input and the outputs routed as displayed below. Name the channels as displayed below. Make sure to option click on all of the sends on the tracks and Disable All Sends on all of the Beds. This will prevent latency from delay compensation becoming disabled by the effects routing we are going to do. **** After you set up the following LFE and Reverb Return channels you need to come back to the beds and select Monitor to In.
Create a return track in Live for the LFE and route the output Audio to LFE (Bed ch4. ***don't assign to Ext out). I made Return A the LFE in my template and I added the following devices on the LFE to add harmonics to the lows with pedal and a LPF to make sure the LFE just receives low frequencies only. Use the corresponding send to send signal to the LFE. Be sparing with sending to the LFE as all of the speakers in an immersive audio setup will already have bass management which will crossover any lows and send them to the sub already.
Set up an immersive multi-channel reverb
Create a Return track and set Audio to - Sends Only. Make sure there are no devices on the return track.
Then create 5 audio tracks and set the Inputs from the Return you just created and set the Outputs as seen below (not to Ext out but to the audio channel beds). Make sure to set monitor to In and option click the sends and Disable All Sends.
Add a reverb to each channel and make sure to slightly change parameters on each one to "de-correlate" the audio so that each speaker is getting unique information that won't phase and/or cause "Big Mono". One fun technique is to set a progressively longer pre-delay into the speakers C(0ms) - LR(10ms) - Sides(30ms) - Top(45ms) - Rear(50ms)
Dolby Atmos Binaural Settings Plug-in
On the same track in Live as the LTC plug-in, I put the Dolby Atmos Binaural Settings Plug-in. This allows you to set binaural depth placement to off, near, mid and far for each track. These settings don't affect the mix in speakers and don't affect apple spacial audio as they have thier own binaural render that disregards these settings. Using Mid sounds most like apples spacial audio.
***Percussive sounds, bass and lead vocals tend to work best set to off or near and set everything else to taste.
Channel 4 LFE I set binaural settings to Off
I use object 127/128 for the stereo Reference Track and set the binaural to off so I can compare my Atmos Mix to the stereo mixed version easily. I need to turn down the stereo version usually about 10dB to compare. I leave the reference track muted and set the key command "R" to the solo button to hear it.
Target Mixing Levels for Dolby Atmos
For individual tracks, all deliverables must achieve an integrated Dolby Atmos loudness that does not exceed -18LUFS
For individual tracks, the amount of peak limiting indicated for binaural headphone playback should not exceed 3dB.
All deliverables must achieve a True Peak measurement that does not exceeed -1 dBTP.
Recording a Master Atmos Mix into the Dolby Renderer and file exporting
Make a New Master File
In the renderer you can create punch in and out points to record a
master file or just manually hit record.
Make sure sync is on and hit the "O" button to record.
After you have recorded the master to play it back in the renderer, click the source to Master. Remember if the renderer is still in sync that you have to play from Live to trigger the LTC.
Export ADM BWF file to send for Atmos Mastering or for distribution.
File export Audio - ADM BWF. The ADM file shows up as a very large .wav file as it contains up to 128 tracks with 3D panning metadata.
The ADM file will not play back properly on regular devices as a reference mix as it needs to be decoded.
To export a reference binaural headphone mix (for reference only) click on the Window menu - Re-renders
Choose the BIN layout (binaural) and click Add
Then click the numbers below Map to live re-renders to add it.
Then File -> Export Audio -> Re-renders
Select the BIN re-render then click export create a reference .wav file of the binaural headphone mix.
