如何让笔记本发出蜂鸣声？
How to ring the system bell from command line?
Why does the bell character have a limit?
Beep in shell script not working?
控制声音的GUI程序
pavucontrol
pasystray、avahi
pavumeter
Alsamixer https://wiki.ubuntu.com/Audio/Alsamixer
alsa-utils
alsamixergui
aumix
alsa-tools-gui https://community.linuxmint.com/software/view/alsa-tools-gui
qasmixer
Advanced Audio Control on Linux
Advanced Linux Sound Architecture
我目前正在使用的是 pasystray ，启动后在系统托盘中显示一个喇叭图标。
音频工具
Home | JACK Audio Connection Kit
jackaudio/jack2: jack2 codebase
duncanthrax/scream: Virtual network sound card for Microsoft Windows