Skip to content

How to change the volume level

If one or a few of your sound sources have higher or lower volume level than the others you might want to adjust it. There are two ways to do that: through Flussonic configuration file or through Flussonic UI. We will provide you with both and you will choose the one that suits you best.

The value can be specified in decibels (dB) or it can be an integer/float (3, 0.5, etc.). By default it equals to 1.

  • If it is just an integer or a float, the output audio volume is calculated by this formula:
    output_volume = avol * input_volume
  • If specified in decibels (dB), the output audio volume is calculated by slightly different formula:
    output_volume = input_volume +/- avol,
    depending whether it is a positive (+9dB) or a negative value (-6dB).

Note: Do not forget to use plus ("+") or minus ("-") when specifying the value!

Through Flussonic configuration file

To change the volume level of the transcoded stream in Flussonic Media Server you have to add the parameter avol in the description of the stream in the configuration file (/etc/flussonic/flussonic.conf) as follows:


stream example1 {
  url udp://239.0.0.1:1234;
  transcoder vb=copy ab=128k acodec=aac avol=2;
}

By default avol=1. In the example above we increase the volume level by 2: avol=2. Then if you specify avol=0.5, it will be halved:


stream example2 {
  url udp://239.0.0.1:1234;
  transcoder vb=copy ab=128k acodec=aac avol=0.5;
}

The following example shows the value specified in decibels (dB) that reduces the original value by an amount of 6 dB:

Note: Do not forget to use plus ("+") or minus ("-") when specifying the value!


stream example3 {
  url udp://239.0.0.1:1234;
  transcoder vb=copy ab=128k acodec=aac avol=-6dB;
}  

Through Flussonic UI

You can change volume level via the Flussonic UI:

  1. Open the Flussonic UI.
  2. Go to Media -> Streams and click on the name of the stream you would like to change the volume level of (in the following example it is channel1_1):

Channel1_1 example

  1. Go to Transcoder:

Transcoder tab

  1. You will see the Audio settings. Set the value in the Volume section. By default it equals to 1:

Volume section

Note: Do not fotget to use unlike signs ("+" or "-") when specifying the value. Otherwise, if you try to set the value in decibells (dB) without plus ("+") or minus ("-") you will receive a warning as follows:

Warning

Now you know how to change the volume of the transcoded stream in Flussonic Media Server.