audacious-plugins software package provides Base plugins for audacious, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install audacious-plugins
audacious-plugins is installed in your system.
Make ensure the audacious-plugins package were installed using the commands given below,
$ sudo dpkg-query -l | grep audacious-plugins *
You will get with audacious-plugins package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Sound |
| Package | audacious-plugins |
| Version | 3.7.2-2+b1 |
| Description | Base plugins for audacious |
| Sub Section | Sound |