Multichannel audio

In this chapter you can find tools, tutorials, system settings and tips & tricks on how to create multichannel audio set-ups

Multichannel audio in Isadora and Reaper

With Isadora you have control over your interactive performance with audio over 2 channels or more. You can work with this Isadora example file and audio files:

https://nextcloud.hku.nl/s/Bs5qoDqGHsLXdGo

here is a usefull tutorial about working with multichannel audio in Isadora: https://support.troikatronix.com/support/solutions/articles/13000084953-tutorial-getting-started-with-multi-channel-audio-in-isadora-3-0-8

In Reaper (audo software or DAW) you can prepare your audio file with multiple channels if you want to use your audio file in a conventional way by playing linear from start to finish or looping it. This should also be possible in other DAW's. Each channel can send your audio to a different speaker depending on your setup you can work with a 2, 4, 8 etc speakers.

Make a mutichannel audio file in reaper:


READ this first!

Mac only!

Download and install BlackHole audio plugin https://existential.audio/blackhole/download/?code=1579271348

You need this to create virtual outputs so you can create multichannel audio files in Reaper (or any other audio edit software) without having an actual multichannel setup at hand.

Restart your computer Open your audio edit software (Reaper) Go to preferences and go to Audio > Device, choose BlackHole 64ch in your Audio Device settings

This is created by Simone, for questions: simone.vandordrecht@hku.nl

4 speaker setup

In this example we work with Reaper, Focusrite interface, 4 speakers, windows desktop.

The idea is to place the speakers in a square position so you can hear the audio coming from different directions. 

Software to be installed:
Reaper we work with Reaper because its free and relatively easy to setup, but there is more software to use for 4 channel setups (like Ableton or Isadora), depending on your needs
Focusrite control software (make sure you choose for the right device, Focusrite interfaces come in different types and versions which all have own control software environment)

Work with mono files

In most conventional audio setups we use 2 channels (left and right) and the audio source file is stereo (2 channels). Since we use a 4 speaker setup, we use 4 audio tracks in Reaper. Thus we have to use a mono (1 channel) audio file. Each mono file will be placed in one of the 4 single channels of reaper. If your source file is stereo you need to convert your files to mono first.
With Reaper follow this short tutorial https://www.youtube.com/watch?v=jLr0FPxd3K0&t=20s
Save the file:

save mono file reaper.png

Connect Focusrite interface

Open Focusrite control software
In the Output Routing tab Change stereo Monitor en Line outputs to mono by clicking [stereo]

To be able to hear anything through channel 1 & 2 you need to TURN UP THE MAIN VOLUME on the interface, or else you only hear channel 3 & 4 ;)

Screenshot 2024-08-29 at 15.29.52.png >>>>>>>>>>>>>>>>>>>>Screenshot 2024-08-29 at 15.31.13.png

Create your Reaper multichannel audio file

In Menu > Reaper > settings you should be able to locate Audio Device > Scarlet (your Focusrite interface), choose Apply & OK

Use command T(mac) or control T(windows) to make 4 tracks. Place your mono audio files on your tracks

View > Routing Matrix & Mixer

In the Routing Matrix change your settings so it looks like this:


Screenshot 2024-08-29 at 15.45.30.png

Now you should be able to play your audio through the 4 channels. 

In the Focusrite control software you can adjust the level of volume of the different channels. change 3 & 4 so it matches 1 & 2. 

Next step might be to automate the volume levels of the audiotrack from other software with MIDI or OSC... depending on the software you use in conjunction with Reaper. Any requests? Send an email to blackbox.ibb-pastoe@hku.nl & blackbox.oudenoord@hku.nl we'll get back to you on that!