For your first question, you’ll only need to add more inputs in the icecast2 configuration. Open the icecast2 configuration:
sudo nano /etc/icecast2/icecast.xml
near the top, you’ll see some lines like:
…change the number of “sources” to 3 or whatever you desire. Save your changes and restart icecast2 service:
sudo service icecast2 restart
Now when you create a 3rd stream in Libretime it will work fine.
For enabling AAC—for a stock Ubuntu 20.04 you are probably running on icecast v.2.44, which does seem to support AAC. Does for me anyway.
But I notice that the stock liquidsoap for that release is v.1.4.2. When I query mine for what input and output codecs are included I get:
+ stream decoding
** Stream decoding methods.**
Use libfaad to decode any stream with an appropriate MIME type.
Decode a AIFF stream with an appropriate MIME type.
Use ffmpeg/libav to decode any stream with an appropriate MIME type.
Use libflac to decode any stream with an appropriate MIME type.
Use libmad to decode any stream with an appropriate MIME type.
Decode as OGG any stream with an appropriate MIME type.
Decode audio/basic as headerless stereo U8 PCM at 8kHz.
- RAW AUDIO
Decode a WAV stream with an appropriate MIME type.
+ stream encoding formats
** Methods to encode streams.**
- video converters
Methods for converting video frames.
From this it looks as though the stock liquidsoap shipped with Ubuntu 20.04 is equipped to decode AAC but I don’t see any encoder listed. I don’t know why.
You could explore compiling your own liquidsoap and including a AAC encoder. I have to tell you that I’ve tried that myself and I did not succeed at getting my compiled liquidsoap to work with Libretime. It’s possible that I simply was not persistent enough at ferreting out file paths and such but it was very daunting to me.
If you would like to include an audio stream with better quality than mp3 have you considered OPUS? OPUS seems to work out of the box with Libretime Alpha12.
Perhaps someone else here has succeeded at custom-compiling liquidsoap and then connecting it in as a daemon service as is required for Libretime and they can share how to do that.
I too used Airtime for about 5 years. It worked…with some issues…and my experience for the past two years is that Libretime is a lot more stable and predictable.