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Overview
Overview
Surround Sound in Reaper Using AIIRA Decoder
Surround Sound in Reaper Using AIIRA Decoder
For Reaper, Ambisonic decoding is handled by the AIIRA Decoder from the IEM Plugin Suite, using a custom configuration file tailored to this room. You can download the plugin suite here.
1. Create and Configure Tracks
1. Create and Configure Tracks
Add Two Tracks
Designate the first as the Ambisonic Bus and the second as the Audio Source.
Organize Tracks into a Folder (fig. 1.1):
In the track control panel (left pane), click the folder icon at the bottom left of the Ambisonic Bus track to convert it into a folder.
Ensure the Audio Source track is nested within this folder, indicating it's part of the bus.
Configure Ambisonics Bus track (fig. 1.2):
Navigate to the mixer panel (bottom pane) and click the routing button on your Ambisonics Bus track. The routing button looks like a series of parallel diagonal lines.
In this routing window, ensure that the Master send tick box is disabled.
Set Track Channels to 16. Note that we will not be using all 16 channels.
Add a new hardware output and select Out 1 / Out 2
In the dropdown menu on the bottom left corner of the routing window, select Multichannel Source > 12 channels > 1-12
Configure Audio Source track (fig. 1.3):
Open the routing window for your Audio Source track.
Set Track Channels to 12
Ensure "Parent send channels from/to:" box is enabled, and that it is sending to "1-12"
2. Insert the AIIRA Decoder
2. Insert the AIIRA Decoder
Add AIIRA Decoder to the Ambisonic Bus:
In the track control panel, locate the Ambisonic Bus track and click the FX button to open the effects window.
Insert the AIIRA Decoder from the IEM Plug-in Suite.
Import Speaker Layout (fig. 1.4):
Within the AIIRA Decoder interface, click "Import".
Select and load the Steinert213-try3.json file, which contains the specific speaker configuration for the studio. You can download the file here (it is also saved on desktop of the studio computer).
Calculate the Decoder:
After importing the layout, click "Calculate Decoder" to generate the appropriate decoding matrix tailored to the studio's speaker setup. Ensure the Decoder Order is "3rd".
Use the available "Noise" buttons to test each speaker.
Fig 1.1 Track 2 should be nested within track 1
Fig 1.2 Routing window settings for Ambisonics Bus track
Fig 1.3 Routing window settings for Audio Source track
Fig 1.4 The AIIRA Decoder should look like this once you've imported Steinert213-try3.json
3. Encode Stereo Audio Sources
3. Encode Stereo Audio Sources
To convert mono/stereo audio source tracks into a multichannel Ambisonics format:
Insert StereoEncoder on the Audio Source Track:
Configure the StereoEncoder or other panning and transform tools:
Within the StereoEncoder interface:
Ensure the Ambisonics order is set to 3rd.
Adjust the Azimuth and Elevation to position the audio source within the 3D sound field as desired. Adjust width as desired.
Reaper is now ready for spatial audio.
Other Useful IEM Plugins
Other Useful IEM Plugins
BinauralDecoder
BinauralDecoder
If you're working with headphones or a stereo speaker setup, you can monitor the Ambisonic mix binaurally:
Add BinauralDecoder to the output track:
On your output track (Ambisonics Bus or Master track depending on how you configured your project), click the FX button.
Insert the BinauralDecoder from the IEM Plug-in Suite.
Configure the BinauralDecoder:
Within the BinauralDecoder interface, ensure the Ambisonic order matches that of your project.
This configuration allows you to experience the spatial mix through headphones, simulating a 3D auditory environment.
EnergyVisualizer
EnergyVisualizer
To gain visual insights into the spatial distribution of your audio:
Insert EnergyVisualizer on the Ambisonic Bus:
On the Ambisonic Bus track, click the FX button.
Add the EnergyVisualizer from the IEM Plug-in Suite.
Monitor Spatial Distribution:
The EnergyVisualizer provides a real-time visual representation of the energy distribution within the Ambisonic field. It can be useful to visually track your outputs, especially for troubleshooting purposes
Surround Sound in Logic Pro using Dolby Atmos 7.1.4 (To be updated)
Surround Sound in Logic Pro using Dolby Atmos 7.1.4 (To be updated)
For Logic, spatial audio will be monitored as a Dolby 7.1.4 system. Note that since we have 2 overheads, the other 2 in the 7.1.4 configuration will be empty outputs.
Set Up 7.1.2 Surround Project
When starting a new project, ensure that it is configured under the "Details>Spatial audio" dropdown for Dolby Atmos 7.1.4. If 7.1.4 doesn't show up as an option, selecting 7.1.2 also works.
Existing projects can be switched to Dolby Atmos mode by going to File>Project Settings>Audio.
Set Up Input/Output Assignments
Under Logic Pro>Settings>Audio> I/O Assignments, configure the assignments to match fig 2.1. You can do so by selecting "7.1.4" then "ITU", then changing the assignment for "LFE" to some unused output 16 (or any above 11). [Note: we are not currently implementing an LFE channel in this system, and we are not currently utilizing a subwoofer, though this is planned.]
Fig 2.1 I/O Assignments
Configure Atmos Settings
Under the channel strip for "Master", open the "Atmos" plugin window.
Under "Monitoring Format", select 7.1.4 to use the studio speakers.
(For binaural headphone monitoring, select an option under "Binaural". )
Add a Surround Track
Create an audio/instrument track. In the channel strip, ensure the output format is set to either "3D Object Panner" or "Surround". Access the panning window by double clicking the panner.
The 3D Object Panner has a different control for elevation, which may be more intuitive in this setup.
Logic Pro is now ready for spatial audio
Surround Sound in Ableton using Envelop for Live (To be updated)
Surround Sound in Ableton using Envelop for Live (To be updated)
For Ableton, spatial audio will be monitored as a Dolby 7.1.4 system, with decoding handled by Envelop for Live (E4L) plugins.
Set Up Audio Outputs
Navigate to your audio device settings, select UMC1820 as the device, and click on "Output Config". Ensure that all mono and stereo outputs from 1-10 are selected, and colored orange (fig 3.1)
Create the Master Bus
Add a new audio track and insert "E4L Master Bus" effect under the Max for Live category. This track will handle the decoding and routing of your spatial audio.
By default, the E4L Master Bus uses a binaural decoder, allowing you to monitor your spatial audio through headphones/stereo speakers. Select "7.1.4" in the decoder dropdown menu and turn off "Monitor 1+2" to use the studio speakers.
Route the outputs in the "Output Routing" menu according to fig 3.2
Create Audio Tracks
Add new audio source tracks. For each track you wish to spatialize, insert "E4L Source Panner". You could also use other panners, such as "E4L Stereo Panner" or "E4L Mono Panner" depending on your preference.
E4L panners are automatically routed to the E4L Master Bus. Double check that your audio track outputs to "Sends only", and that your E4L Master Bus outputs to "Master".
Ableton is now ready for spatial audio
Fig 3.1 Output configuration
Fig 3.2 Output routing in the E4L Master Bus
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